- Avengers (Disbands)
- Hawkeye / Ronin (Clint Barton) (Rejoins and leaves team)
- Iron Man / "Howard Potts" (Tony Stark) (Death)
- Nebula (Joins and leaves team; rejoins Guardians of the Galaxy)
- Captain America / Captain Stevens (Steve Rogers) (Last appearance) (Main story and flashback) (Impersonates Captain America) (Leaves team)
- Hulk (Dr. Bruce Banner) (Impersonates Hulk) (Leaves team)
- War Machine (James "Rhodey" Rhodes) (Leaves team)
- Black Widow (Natasha Romanoff) (Death)
- Rocket (89P13) (Joins and leaves team; rejoins Guardians of the Galaxy)
- Thor (Leaves team; joins Guardians of the Galaxy)
- Ant-Man (Scott Lang) (Joins and leaves team)
- Avengers (Disbands)
- Rescue (Pepper Potts) (First appearance as Rescue)
- Dora Milaje
- Gamora (First appearance) (Leaves Black Order)
- Black Panther (King T'Challa) (Rebirth)
- Princess Shuri (Rebirth)
- Masters of the Mystic Arts
- Guardians of the Galaxy
- Jabari Tribe
- Numerous unnamed members
- White Wolf (Bucky Barnes) (Rebirth)
- Wasp (Hope van Dyne) (Rebirth)
- Thanos (Death)
- Thanos (Only appearance; dies)
- Black Order (Only appearance) (Disbands)
- Lila Barton (Death and Rebirth)
- Laura Barton (Death and Rebirth)
- Cooper Barton (Death and Rebirth)
- Nathaniel Barton (Death and Rebirth)
- Erik Selvig (On-screen)
- Sharon Carter (On-screen)
- Peggy Carter (Photo)
- Jim (Only appearance)
- Cassie Lang
- Morgan Stark (First appearance)
- F.R.I.D.A.Y. (Voice)
- Bor (Mentioned)
- Dr. Jane Foster (On-screen)
- Malekith (On-screen)
- Frigga (Mentioned)
- Gamora (Mentioned)
- Avengers (Only appearance)
- Ancient One (Only appearance)
- Dr. Stephen Strange (Mentioned)
- Loki (First appearance) (Impersonates Captain America)
- Loki (Only appearance)
- Frigga (Only appearance)
- Einherjar (Only appearance)
- Ronan the Accuser (Mentioned)
- S.H.I.E.L.D. (Only appearance)
- S.T.R.I.K.E. (Only appearance)
- Agent Jasper Sitwell (Only appearance)
- Secretary Alexander Pierce (Only appearance)
- Nick Fury (Mentioned)
- Several unnamed others (Only appearance)
- Hydra (Only appearance)
- Doctor List (Mentioned)
- Bucky Barnes (Mentioned)
- Odin (Mentioned)
- Odin (Mentioned)
- Thor (Mentioned)
- Star-Lord (Peter Quill) (Only appearance)
- Dr. Jane Foster (Only appearance)
- United States Army (Only appearance)
- Stan Lee (Only appearance)
- Captain America (Steve Rogers) (Photo)
- S.H.I.E.L.D. (Only appearance)
- Maria Stark (Mentioned)
- Howard Stark (Mentioned)
- Edwin Jarvis (Only appearance)
- Red Skull / Stonekeeper (Johann Schmidt) (Only appearance)
- Ivan (Mentioned)
- Edith Barton (Mentioned)
- Karen (Behind the scenes)
- Aragorn (First appearance)
- Happy Hogan
- May Parker
- Dr. Hank Pym (Rebirth)
- Janet Van Dyne (Rebirth)
- Harley Keener
- Secretary Thaddeus "Thunderbolt" Ross
- Maria Hill (Rebirth)
- Nick Fury (Rebirth)
- Ned Leeds (Rebirth)
- Queen-Mother Ramonda
- Vision (Mentioned)
- Peggy Carter (Only appearance) (Only in flashback)
Races and Species:
- Humans (Main story and flashback)
- Xorrians (Mentioned)
- Sakaaran Natives
- Dark Elves (Mentioned)
- Chitauri Apes (First appearance)
- Flora colossi
- Winged Horses
- United States of America
- Mexico (Mentioned)
- Germany (Mentioned)
- Leipzig/Halle Airport (Mentioned)
- Toronto (Mentioned)
- Budapest, Hungary (Mentioned)
- The Garden / Planet 0259-S (Real name first revealed)
- Quantum Realm
- Astral Plane
- Harokin (Mentioned)
- Alternate 2012 A.D. (Only appearance)
- Earth (Only appearance)
- United States of America (Only appearance)
- New York (Only appearance)
- United States of America (Only appearance)
- Earth (Only appearance)
- Alternate 2013 A.D. (Only appearance)
- Alternate 2014 A.D. (Only appearance)
- Alternate 1970 A.D. (Only appearance)
- Alternate 1949 A.D. (Steve and Peggy are married) (Only appearance) (Only in flashback)
- Hawkeye's Bow
- Trick Arrows
- Iron Man Armor MK L
- Captain Marvel's Suit
- Universal Neural Teleportation Network
- Captains America's Uniforms
- Black Widows' Suits
- Black Widows' Gauntlets
- Black Widow's Batons
- War Machine Armor MK IV
- Hulkbuster Armor 2.0
- Infinity Gauntlets
- Ant-Man's Suit and Helmet
- Pym Particles
- Iron Man Armor MK VI (First appearance)
- Captains America's Shields
- Iron Man Armor MK VII
- Arc Reactor
- Eye of Agamotto
- War Machine Armor MK V (First appearance)
- Iron Man Armor MK LXXXV (First appearance)
- Loki's Sceptre
- Infinity Stones (Only appearance)
- Star-Lords' Helmet
- Awesome Mix Vol. 1
- Quad Blaster
- Translator Implant
- Gamora's Swords
- Proxima Midnight's Spear
- Corvus Glaive's Glaive
- Cull Obsidian's Hammer
- Panther Habit
- Vibranium Strike Gauntlets
- Exo-7 Falcon Flight Harness
- Cloak of Levitation
- Sling Ring
- Shield of the Seraphim
- Drax's Knives
- Iron Spider Armor
- White Wolf's Bionic Arm
- Wasps' Suits and Bio-Synthetic Wings
- War Machine Armor MK VII (First appearance)
- Iron Man Armor MK XLIX (Rescue Armor) (First appearance)
- M'Baku's War Club
- Shield of the Seraphim
- Winds of Watoomb
- Sanctuary II (Destroyed)
- X-Con Van with Hank Pym's Portable Lab (Destroyed)
- Dragon Flyers
In 2018, Clint is living out his last few days under house arrest. He teaches his daughter Lila how to shoot a bow and arrow, being called by his wife to join the family for hotdogs. Laura asks if anyone wants mayo on their hotdogs, confusing Clint, Lila and her brother Cooper. When Laura asks her youngest son Nathaniel what he wants, he bluntly asks for ketchup. Clint walks over to join the family at their table, calling for Laura to join them. However, he turns around to see she's vanished. He turns back to see the rest of the family has also vanished. Panicked, he runs around yelling for them. (Unknown to Clint, half of all the life in the universe had just been wiped out by Thanos at the moment; his family were the unlucky ones in the random culling.)
Fast-forwarding a little...
Following their fight with Thanos on Titan, Tony and Nebula discover that the Guardians of the Galaxy's ship suffered damage in the battle (likely from the moon debris Thanos rained down on them). They manage to repair the damage enough to get two days worth of power out of the ship; however, it runs out of juice in the middle of nowhere, stranded too far from any civilization for help. Rather than simply give up, Tony decides to bide time in the hopes someone will arrive; he plays games with Nebula, who starts bonding with him and treating his stab wound. After 22 days, they are out of food and will lose oxygen in a few hours. Tony records a goodbye message for Pepper, drifting off to sleep. However, his rest is interrupted by an orange glow approaching the ship. He looks out the window to see its coming from none other than Captain Marvel.
On earth, the Avengers are still reeling from their defeat and trying to figure out who on Earth was a victim of the snap. Captain Marvel brings Tony and Nebula to the Avengers compound, much to their relief. Tony is happy to see Pepper survived, sharing a moment with her. Rocket joins Nebula on the stairs of the ship, both mourning the loss of their surrogate family. After being brought up to speed, Tony snaps at Rogers for his failure; he reminds him about the idea he gave about a suit of armor around the planet (which lead to Ultron, due to Wanda giving him a vision of his worst fear two years ago), and that Rogers told him they'd lose together if they couldn't protect the world. Tony gives his nanotech armor to Rogers, bitterly telling him to go find Thanos and have another go; he passes out and is put in the med bay on IV to recover.
However, Rocket and Nebula have some good news; when the snap occurred, it released a unique cosmic ripple effect across the universe. A few days ago, a similar one happened on a planet called Titan II, which Nebula reveals to be where Thanos planned to retire after completing his life's work. As Tony is too badly malnourished, Cap, Nat, Bruce, Thor, Danvers, Rhodey, Rocket and Nebula head for the planet. Danvers does a sweep of the planet once they arrive, discovering there is no advanced technology and Thanos is the only one on it. Below, a severely hurt and weakened Thanos is humbly cooking dinner. He is surprised by Thor, who cuts off his arm to prevent him from using the stones. Everyone else rushes in, ready to attack. However, Rocket discovers to his horror that the gauntlet is empty of the stones. Thanos reveals that their power would only tempt him after completing his work, so he destroyed them using the stones' own power to ensure the culling can not be undone. In a rage, Thor decapitates Thanos, remembering the Mad Titan's taunt about not going for his head.
Five years later... 2023
The Earth has more or less returned to proper stability. Rogers is leading a support group of survivors, encouraging them to move on from their losses. At the Avengers Facility, Nat is on a video call with Okoye, Rhodey, Danvers, Rocket and Nebula about progress in stabilizing Earth and the rest of the universe; Danvers, Rocket and Nebula are busy quelling chaos on other worlds, while Okoye and Rhodey are keeping an eye on Earth. Once the other four hang up, Nat asks Rhodey about Clint's location; he reveals a Mexican cartel was wiped out recently. Since the loss of his family, Clint has gone on bloody crusade to "rectify" the Blip's mistake in leaving criminals alive. (Due to the still-turbulent society, Clint can't be caught due to the lack of manpower; putting him on trial if he was caught would likely not work either, as many people would be siding with his decision to wipe out criminals out of their grief.) Rogers joins her, joking that Thanos wasn't all wrong, as the water is cleaner and there's less pollution. Elsewhere, Luis's van with the tunnel to the quantum realm has since been put in an impound lot; a rat accidentally steps on the activation button and Scott Lang is spat out, confused by his surroundings. After getting the security guard to let him out with the equipment, Scott is shocked to see the effects of the snap. He races to his ex-wife's house to see if his daughter is still alive; to his shock, he is greeted by an early teen version of Cassie, who is happy to see her father again.
Lang goes to the Avengers Facility, surprising Nat and Rogers. He explains that time moves differently in the quantum realm; he was in there for five hours, basically an hour for each year. He theorizes that they can use this time dilation to their advantage and use time travel to bring past versions of the Infinity Stones to the present day and reverse the snap's effects. They go to ask Tony for help, but he is unwilling to jeopardize the life of his four year-old daughter Morgan. Knowing only one other genius, Nat and Rogers take Lang to see Bruce Banner, who is now a celebrity as the Hulk, having figured out how to maintain his mind and have the strength of the Hulk. Their experiments with time travel accidentally alter Lang's age briefly, only to have Tony arrive and reveal that he is willing to help them (if it means they can bring back his protege/surrogate son Spider-Man). Nat recruits Clint for the mission, while Nebula, Rocket and Rhodey return. They also go to New Asgard to recruit Thor, who has become an overweight bitter drunk to forget his troubles; when offered redemption, Thor agrees to join. Once the group is assembled, Bruce explains that unlike EVERY single time travel movie everyone has seen, anything they do in the past will NOT alter their present day; instead, it will create alternate realities, meaning they don't have to worry about the timeline. Lang explains that without Hank Pym to create more Pym particles, there's only enough left for 10 round trips - a particle for each trip. Tony reveals he create devices to control when they go in time, which is in wrist-worn form.
As everyone has "damn-near been killed" by a stone (except Lang), they go over all the times they seen the stones in the past to figure out locations. While brainstorming with Tony and Bruce, Nat realizes that they can obtain three stones at the same time if they pick the right year. Choosing New York 2012 (for the tesseract, Loki's scepter and the Eye of Agamotto), Morag 2014 (for the orb and a trip to Vomir) and Asgard 2013 (for the Aether), the group divides into three teams. Tony, Rogers, Bruce and Lang will go to 2012, Nebula, Rhodey, Clint and Nat will go to 2014 and Thor and Rocket will go 2013.
Arriving in New York 2012 just after Bruce transformed into the Hulk to join the fight, Tony, Rogers, Lang and Bruce watch as the Hulk smashes Chitauri from an alley, embarrassing Bruce. Bruce is to go the Sanctum Sanctorum for the Time Stone, while they get the Space and Mind Stones after their past selves arrest Loki. Arriving on the roof of the Sanctum, Bruce finds the Ancient One blasting Chitauri away. She reveals that he's four years too early to find Dr. Strange there, but Bruce insists she hand over the Time Stone. The Ancient One pushes Bruce's astral form out of his body and reveals that taking the Stones from their places in time will cause chaotic alternate timelines as the stones maintain balance. Bruce understands, explaining that once they are done with the stones in the future, they will return them. In Stark Tower, Tony tells Lang how to give his past self a mild heart attack by unplugging part of his Arc Reactor. This distraction allows him to take the case with the Tesseract in it, but unfortunately, Hulk bursts through the stairs, angry at being forced to use them; the case opens and lands near Loki, who uses it to vanish. Elsewhere, Rogers joins Agents Sitwell and Brumelo in the elevator as they prepare to take Loki's scepter to Dr. List. He whispers "Hail HYDRA" to Sitwell, tricking him into thinking he's joined HYDRA. Unfortunately, 2012 Rogers mistakes his 2023 self for Loki in disguise, leading to the two of them fighting; distracting his past self by telling him Bucky is still alive, Rogers knocks himself out and returns to his team's arrival point. Tony reveals that they have an option for the Tesseract and more particles in 1970; they entrust Lang with the scepter and he returns to the present.
Arriving in 1970, Tony reveals that they are at an SSR/S.H.I.E.L.D. base where they've been keeping the Tesseract and where Hank Pym is still working for S.H.I.E.L.D. Rogers makes a call to Pym, telling him that some soldiers opened a dangerous package of materials he needs for his work, tricking him out of his lab. Hiding in an office to briefly avoid security, Rogers sees it belongs to his love Peggy Carter. Tony manages to get the Tesseract in a briefcase but runs into his father Howard. Tony passes himself off as Howard Potts, learning his father was worried about how to raise him. Telling him that he's got a daughter, Tony subtly encourages his father to not worry about how to raise his child. Reuniting with Rogers, they both return to the present.
In 2013 Asgard, Thor spots Jane being escorted around the palace, having a breakdown. Rocket encourages him to talk to Jane long enough for him to extract the Aether from her. However, the very next moment, Thor vanishes to watch his mother Frigga. Frigga spots Thor, immediately realizing he's the future version of her son. Thor asks for her council, and they return to her room. In the meantime, Rocket extracts the Infinity Stone from Jane, alarming everyone. He rejoins Thor, who calls for Mjolnir, discovering that he is still worthy of it. They return to the present.
In 2014, Nebula, Rhodey, Clint and Nat arrive at Morag. Clint and Nat head to Vomir on a craft from Quill's ship, while Nebula and Rhodey knockout Quill to get the Power Stone before him. When they prepare to return, only Rhodey does; Nebula becomes paralyzed due to her cybernetics accidentally linked with 2014 self, allowing 2014 Thanos to learn of their plan. He kidnaps her and disguises her past self as her, sending her to the present to allow his arrival in that time. On Vomir, Nat and Clint meet the Red Skull, who reveals the Soul Stone can only be retrieved by giving up a loved one. Nat sacrifices herself, as she has no family other than the Avengers. A devastated Clint returns to the present.
In 2023, everyone returns at the same time, learning of the Soul Stone's price. Mourning her briefly, Tony uses his nanotech to create a new gauntlet. Bruce offers to snap his fingers, as his Hulk body is resistant to the stones' gamma radiation. Right as he snaps his fingers, 2014 Nebula activates the time machine, allowing Thanos's ship to begin its arrival. Once the snap occurs, Clint is happily surprised to get a call from his wife. Lang notices more birds outside, coming to the conclusion they've won. However, Thanos' ship arrives and destroys the compound. 2014 Nebula is instructed by her father to retrieve the stones so he may redo his work. In the meantime, Outriders are attempting to hunt down Clint, who has the gauntlet; Bruce, Rocket and Rhodey are trapped under rubble with water slowly rising. Lang is racing to their location to help. 2014 Nebula finds Clint and takes the gauntlet, only to be confronted by 2023 Nebula and 2014 Gamora, who was won over by Nebula's sisterly love. Having not experienced the events that helped 2023 Nebula change, the 2014 version attempts to kill them; however, 2014 Nebula is killed by the original before she can harm 2014 Gamora.
Tony, Rogers and Thor look out from the rubble in utter shock at the sight of Thanos. Pissed off and not caring its a trap, all three engage him in battle, as Thanos reveals he will rebuild the universe after the devastation, so no-one will attempt this again. They fight him with Thor using both Mjolnir and Stormbreaker to attempt decapitating Thanos with Rogers holding Thanos in a headlock; however, because this version was not weakened severely from using the Infinity Gauntlet, his flesh is still resistant to most harm. Thanos pins Thor, about to kill him; however, Mjolnir flies past Thor and into the hands of Captain America (which Thor foresaw was possible back when they fought Ultron). Thanos calls upon his Chitauri and Outrider armies to kill the Avengers.
Rogers receives a call from Falcon, telling him he's on his left. A portal appears, and T'Challa, Shuri and Okoye step out of it, followed by Falcon. Acknowledging each other, T'Challa yells to his Wakandan army to prepare for battle. More portals opens up, with the Guardians of the Galaxy, Doctor Strange, Spider-Man, Wanda, Bucky, Pepper, Wasp, Valkyrie, the Masters of the Mystic Arts, the Ravengers, and the army of Asgard all marching out of portals to join the battle. Lang emerges from the rubble as Giant-Man moments later, carrying Rocket, Bruce, and Rhodey ready for battle. Dr. Strange asks Wong if this was everyone, making him ask if he wanted more fighters. Rogers fastens his shield and grabs Mjolnir, ordering for the Avengers to assemble. With that order, both side erupt into a massive battle. Clint asks Rogers what he's supposed to do with the Infinity Stones, to which he orders them be taken far away from Thanos. As a result, a game of hot potato starts with the gauntlet, with it being tossed to other heroes in an attempt to get it to the Quantum Tunnel in Lang's van. Wanda appears before Thanos, enraged for the murder of Vision; using her powers, she tortures the Mad Titan and begins tearing apart his armor. Thanos yells for bombardment from his ship, disrupting the fight briefly.
By this point, Spider-Man has the gauntlet and even the Instant Kill of his suit can't hold off Outriders for much longer. Thanos's ship starts firing at the sky as a blinding light comes down and destroys it; Captain Marvel has returned. Teaming up with Pepper, Valkyrie, Mantis, Nebula, 2014 Gamora, Wanda, Shuri and Okoye, they race to get to the van. However, its destroyed, resulting in the gauntlet flying to Thanos. Dr. Strange nudges Tony to take action; this is the one possibility of them winning he foresaw. Tony struggles to get the gauntlet, but fails. Thanos snaps his fingers to eliminate everyone, but nothing happens. Tony reveals he stole the stones and his armor create a gauntlet for him. He snaps his fingers, causing Thanos and everyone loyal to him to disintegrate. Thanos sits in lament, accepting his fate. Pepper, Rhodey and Spider-Man rush to Tony, but F.R.I.D.A.Y. tells them he hasn't got long. Pepper shares one last loving moment with Tony and he passes peacefully.
Time passes, and Earth celebrates the Avengers' victory, knowing their safety came at the cost of the life of Earth's greatest defender. All across the globe, friends and family are reunited. Lang and Hope visit Cassie, Shuri and T'Challa are reunited with their mother. Peter returns to school, discovering his best friend Need Leeds was among the victims of the Blip that came back as well. A recording Tony made prior to the Time Heist gives a speech about his hopes in that the plan works and leaves a final loving message for Morgan.
A funeral is held a Tony's home, where the a reef is set afloat in the lake, with the frame Pepper once framed his first arc reactor with: Proof that Tony Stark has a heart. In attendance are Pepper, Morgan, Happy, Rhodey, Peter, May, Rogers, Bruce, Thor, Strange, Wong, Lang, Janet, Hope, Hank, Quill, Nebula, Drax, Mantis, Rocket, Groot, T'Challa, Shuri, Okoye, Clint and his family, Wanda, Bucky, Sam, a grown-up Harley Keener, Maria Hill, Thaddeus Ross, Danvers and Nick Fury. After the service, Clint talks to Wanda about how he wishes Nat and Vis could know that they won. Wanda comforts her friend, telling him that they know. Happy tells Morgan he'll look after her, and asks her what he can do; she asks for a cheeseburger, making Happy remember when Tony got rescued from the Ten Rings. He tells her that he'll buy her all the cheeseburgers she wants.
In New Asgard, Thor tells Valkyrie that his mother wisely told him to stop trying to be who he's "supposed to be" and find who he's "meant to be"; he makes her the new ruler of New Asgard officially, as she had more or less been running their society while he was in his drunken stupor. While he has no clue how to go about, he's decided to go back into the universe as a member of the Guardians of the Galaxy in the meantime. In the ship, Quill is looking at Gamora's picture wondering where the 2014 version of her went after the battle. Thor attempts to help Quill with the charts, making him wonder if Thor is trying to be the team leader. Drax, Nebula, Mantis and Rocket suggests fighting for the right to be leader, but both laugh it off. Thor confirms that Quill is their leader.
In the forest outside the Avengers' property, Bruce is about to send Rogers back in time to return the Infinity Stones and Mjolnir. Once he's gone, Bruce counts down and hits the return button, However, nothing happens. Bucky draws their attention to an elderly man sitting not too far away. Bucky urges Sam to go talk to him. Sam realizes the old man is Rogers, asking him what happened. Rogers reveals that after he put everything back, he decided to get a life like Tony told him; it was a beautiful one. He hands Sam his shield, naming him the next Captain America. Sam is honored, telling him he'll do his best to honor his title. Seeing a wedding ring, Sam asks about Rogers' wife; however, Rogers decides not to tell him. Flashback to the 1940s, Rogers is dancing in his home with his wife. It turns out to be none other than his first love Peggy Carter.
- Chris Evans as Captain America / Steve Rogers
- Patrick Gorman was the body double for the elderly Rogers
- Paul Rudd as Ant-Man / Scott Lang
- Jackson Dunn portrays Scott at 12 years old
- Lee Moore makes a posthumous appearance as 93-year old Scott
- Bazlo and Loen LeClair portray Scott as a baby
Additionally, Lexi Rabe portrays Morgan Stark. Ross Marquand reprises the role of Red Skull/Stonekeeper. Co-director Joe Russo (credited as Gozie Agbo) and Thanos co-creator Jim Starlin cameo as grieving men. Cassie Lang in 2023 is now portrayed by Emma Fuhrmann. Michael Shaw and Terry Notary reprise their roles as Corvus Glaive and Cull Obsidian, respectively. Kerry Condon returns to voice F.R.I.D.A.Y. Ben Sakamoto, Ava Russo, and Cade Woodward portray Cooper, Lila Barton, and Nathaniel Barton, respectively. Stan Lee cameos as a hippie driver. Community alumni Yvette Nicole Brown and Ken Jeong make cameo appearances in the film. Callan Mulvey reprises his The Winter Soldier role Agent Jack Rollins. Co-director Anthony Russo's son Julian, niece Lia, and nephew Auggie portray Hulk fans. Ty Simpkins reprises his role as Harley Keener from Iron Man 3. Matthew Berry cameos as a SHIELD agent.
Carrie Coon doesn't reprise her voice role as Proxima Midnight, but Monique Ganderton still provides the motion capture for the character. Katherine Langford shot a scene as a grown-up Morgan Stark, but the scene wasn't included in the final cut of the film. Paul Bettany doesn't reprise his role as the Vision, although previously indicating he would.
- The film was announced during Marvel Studios' event at El Capitan Theatre on October 28, 2014.
- Although Avengers: Infinity War - Part II was the film's original title, the Russo brothers later confirmed that "Part I" and this movie would be re-titled to emphasize the differences between the two films, the former being re-titled to Avengers: Infinity War.
- Filming for this film started on August 10, 2017, and wrapped on January 11, 2018. The filmmakers decided to shoot the two Avengers films back-to-back, despite the previous announcement that it would be shot simultaneously.
- The film's title was officially announced as Avengers: Endgame alongside the debut trailer released on December 7, 2018.
- This film broke both the domestic opening weekend and worldwide opening box office records, with around $350 million domestic and $1.2 billion worldwide grosses, beating both records previously set by Avengers: Infinity War ($257.7 million and $640.5 million, respectively).
- Additionally, this film broke the record for the fastest time a film managed to reach $1 billion at the worldwide box office, on its 5th day of release, again beating Avengers: Infinity War which did so on its 11th day.
- On July 20, 2019, this film surpassed the $2,789.7 billion global gross of Avatar, to become the top grossing film of all time at the worldwide box office (not adjusted for inflation), at the time.
- With a worldwide total box office gross of $2,797 billion, this film became the highest-grossing film of 2019.
- According to co-director Anthony Russo, the argument at the center of this movie was whether one can control their own destiny.
- Writers Christopher Markus and Stephen McFeely contemplated having the disappearance of Hawkeye's family happen at the end of Avengers: Infinity War.
- In certain cuts of the movie, Captain Marvel wouldn't be revealed to be responsible of saving Tony Stark and Nebula until after the ship got back to Earth.
- Markus and McFeely struggled to decide where to take Thanos' character from the previous movie. It was Executive Producer Trinh Tran's suggestion to kill him early on.
- The five-year time jump was inspired in part by TV series such as Fargo and Lost.
- The trajectories of the heroes in the film were determined as sort of a What If? scenario.
- When brainstorming ideas for each character's arc, it was considered to have Thor on a mission of vengeance. This idea was scrapped since the character's arc in Infinity War already had consisted of that.
- In an early draft of the film, following the 5-year jump, Steve Rogers would've been living with Sharon Carter, but their relationship would've been turbulent. Carter's role was eventually excised because it was inessential to the plot of the movie.
- An idea directors Anthony and Joe Russo tried to work into the movie was the scenario that roughly a quarter of all children worldwide would've been left orphaned after Thanos' snap. At a point early into development, they worked this angle by having Black Widow lead an organization in Washington, D.C. that was in charge of orphans.
- An idea for the status quo after the 5-year jump was for Jim Rhodes to have become Vice President of the United States.
- Scrapped versions of the script showed that memorials like that in San Francisco existed in every city in the world.
- McFeely wrote scenes of Bruce Banner working in a lab to transform himself into "Smart Hulk." Additionally, in an early version of the plot of Infinity War, Banner would have evolved into Smart Hulk during the battle of Wakanda. Since this plot resolution was scrapped late into development, certain scenes of the first act of Endgame had to be reshot, since they originally made use of Smart Hulk.
- In Tony's bedtime exchange with Morgan, they originally told each other "I love you tons." The expression "I love you 3,000" is a thing that Tony Stark actor Robert Downey Jr.'s children have said to him in real life.
- The element of time-travel was brought to the table by Producer Kevin Feige, who wanted to use the Time Stone, or use time as an element.
- Physicists were consulted for the formulation of the movie's time-travel.
- Test screening audiences were confused by the film's rules of time-travel in comparison to Back to the Future, prompting reshoots of multiple jokes and explanations of the nuances of time-travel, including the scene in which Bruce Banner explicitly dismisses time-travel movies listed by Jim Rhodes and Scott Lang, including Back to the Future.
- The reason Clint's test travel through time is timed is because the Avengers expected that he could want to stay in the past. In a version of the movie's story, Clint attacked the Hulk after being forced to return.
- A scene cut after Clint's return from the past had Scott Lang offer him orange slices as a callback to Captain America: Civil War.
- An unused idea for the movie involved Captain America going to space and travelling the galaxy with the Red Skull as an untrustworthy sidekick to track down the errant Infinity Stones.
- Markus and McFeely initially avoided having the characters time-travel to the Battle of New York since they considered it "pander-y" until co-Director Joe Russo asked for it. In the first draft of the film, the Avengers would have tried to get the Tesseract from Asgard since the artifact was there at one point with the Aether. In this version of the film, Iron Man would have infiltrated Asgard using a stealth armor, but he would have had to fight Heimdall whose abilities would allow him to detect Stark. In this early draft, Thor would have had long scenes with Jane Foster, and the Avengers would've tried to retrieve the Power Stone from Morag when the planet was still flooded.
- In a version of the story in which Scarlet Witch was one of the surviving heroes, she and Rocket went to the Triskelion to get the Tesseract, and would then take a ride to the Sanctum Sanctorum and use its portal into the Kamar-Taj to get the Time Stone.
- The moment in which the Avengers arrive from the future to the Battle of New York was changed in post-production. An early version had the team arrive after Iron Man kills a Leviathan by flying through it and blowing it up from the inside. Test audienced required several minutes to acclimate themselves. Another version had the entry point be when the Hulk beats up Loki like a ragdoll.
- The moment when Hulk imitates his old self in 2012 New York wasn't originally in the movie. Animators did it as a joke, but the Russos liked it and had Mark Ruffalo recreate it with motion capture.
- The color scheme of the Iron Man Armor MK LXXXV, namely the pronounced use of gold in the arms and legs, was chosen to be reminiscent of the Classic Iron Man Armor from the comics.
- There were versions of the movie written with Nick Fury and another with Maria Hill appointed to retrieve Loki's Sceptre from the Avengers. After Alexander Pierce actor Robert Redford announced he was going to retire from acting, Markus and McFeely considered asking him to reprise his role.
- The shots from Asgard of Loki and Jane Foster were repurposed from unused Thor: The Dark World footage. Because of this, Natalie Portman didn't have to step on set once to be in the film.
- A scene scrapped from the film's script had Rocket uncomfortably explain to Jane Foster why and how he had to remove the Aether from her body.
- Scenes with past Nebula were reshot to better explain her having two frequencies of consciousness.
- Howard Stark getting sauerkraut for his wife was inspired by Stephen McFeely's mother craving sauerkraut when she was pregnant with him.
- Peggy Carter was not going to appear in the 1974 sequence in the first draft of the script.
- Drafts of the movie were written with Hawkeye making the sacrifice for the Soul Stone.
- Black Widow's sacrifice was originally shot differently. Clint and Natasha would have been followed to Vormir by Thanos and his army and a small battle ensued. During the fight, Natasha decides to run off the cliff, and Clint tries to stop her while also fending off the attack. Despite test audiences reacting to the scene positively, it was reshot and changed to the final version to make something that serviced Black Widow more.
- The design lines of Hulk's jumpsuit are meant to form a big "H" on his chest.
- An early draft saw all the fallen heroes reunite at the Avengers Facility before Thanos attacks.
- The Russo Brothers dubbed Thanos' younger self as "Warrior Thanos," since he was more precocious and self-confident and "not quite as enlightened," whereas the Thanos from Avengers: Infinity War was mellowed-out and philosophical.
- An idea left unused for the opening of the final battle was that the Thanos from 2014 would have gone to Earth and killed the Avengers of his era, bringing the decapitated head of that timeline's Captain America to taunt the future Avengers.
- A longer version of the film's final battle was written and shot. This climax was going to have its own three-act structure.
- The Avengers entering the Quantum Realm and the Time Hiest scenes are similar to how the Avengers entering and saving Avengers who were struck in multiple realites by the Cabal in the Marvel's Avengers: Secret Wars episode "The Once and Future Kang."
- Hulk holding the rubble of the Avengers Facility is a reference to Marvel Super Heroes Secret Wars #4, in which the Hulk holds a mountain to stop it from crushing the heroes of the story.
- A scrapped scene written for the final battle consisted of a moment in a trench where the battle had gotten paused for roughly three minutes and approximately eighteen characters were going to discuss strategies in a way Markus and McFeely eventually regarded didn't flow like a natural conversation and felt "completely fake" and "fraudulent."
- Hank Pym and Janet Van Dyne were considered to appear in the final battle since they had their own Ant-Man and Wasp suits.
- There was a scene envisioned for the final act in which the Winter Soldier would have saved Iron Man and Rescue in the battlefield. Bucky and Tony would then have had a moment in which Stark forgives him for the death of his parents, or at least have acknowledged that it wasn't his fault.
- In an earlier draft of the movie, 2014's Nebula would have intercepted Stark's Infinity Gauntlet during the final battle. She would have tried to use the glove herself in an attempt to prove herself to Thanos but would have died. This scene would also have doubled as a nod to Infinity Gauntlet #5, in which Nebula wields the Infinity Gauntlet.
- Directors Anthony and Joe Russo sought Robert Downey Jr.'s approval for his character's arc in the film. Downey had mixed emotions about it, but ultimately approved it.
- Various versions of the final confrontation between Thanos and Iron Man were shot; some featured lines of dialogue, others had Robert Downey Jr. improvise, and before the scene was reshot, the scene was silent. It was eventually decided that Thanos needed a moment at the end of the movie where he says something. It was decided to have him echo the final words of his future self to create symmetry.
- Editor Jeff Ford came up with the idea of Tony's "I am Iron Man" retort. Robert Downey Jr. was initially reluctant to reshoot the scene and get into the emotional state required for it. Producer Joel Silver helped convince Downey to do it.
- Katherine Langford was cast as a grown-up version of Morgan Stark, whom Tony would see in a vision after snapping his fingers, mirroring a similar moment between Thanos and a vision of Gamora in Avengers: Infinity War. According to the Russo Brothers, test audiences were confused by the scene, and it was ultimately cut because there was no emotional association with the adult version of Tony's daughter. The main idea behind the scene was to have future Morgan forgive Tony and give him peace before his death. Joe Russo explained that while the idea felt resonate, the movie was already over complicated.
- Tony's death scene was shot without a script. Instead, Robert Downey Jr., Tom Holland, Gwyneth Paltrow and Don Cheadle were only told the context of the scene and given a few directions, the rest was improvised.
- Markus and McFeely wrote a number of dying words for Tony Stark, but Robert Downey Jr. thought it would be much more powerful for Tony to die silently.
- Past Thanos sitting on a rock waiting to die was meant to mirror the character's future self sitting on his porch at the end of Infinity War.
- A scrapped extended version of Tony's death scene had the heroes bending on their knee to honor Stark's sacrifice. The scene additionally showed Gamora slipping away while the heroes were mourning. The scene was filmed prior to Tony Stark's funeral, which the Russo Brothers felt was a more resonant and emotional reflection on Tony's.
- Tony Stark saying "I love you 3,000" at the end of his speech was included during additional dialogue recording, which is why it's delivered off-screen.
- Natasha Romanoff didn't get a funeral because she was a cipher and Markus and McFeely didn't feel it was honest to the character to give her a funeral.
- According to Markus and McFeely, Tony Stark and Steve Rogers' finales mirror each other's story arc; Tony was about moving to selflessness while Steve moved towards self-interest.
- The idea for showing the main cast's signatures in the final credits was inspired by the end credits of Star Trek VI: The Undiscovered Country.
- Kevin Feige had the idea to end the movie with an audio callback to Iron Man to accompany the Marvel Studios logo. The production team dug through the material of Iron Man and found the smithing sounds used in the movie when Tony Stark was building the Iron Man Armor MK I. The sound's rhythm was adjusted slightly for its reuse.
- This is the last Marvel Cinematic Universe film with a cameo appearance from Stan Lee.
- In a non-canon commercial for The Falcon and the Winter Soldier, the identity of "Noobmaster69" was jokingly revealed to be Aaron from Captain America: The Winter Soldier.