And so the time of the Odinsleep came once again to Asgard, when Lord Odin rested, and replenished his power. But this time, Odin's favorite son was not there to protect him while he slumbered. The son had abandoned the Golden Realm, to protect the mortals he loved so dearly. While Balder, Sif, and the rest of Asgard's warriors were ever so pathetically vigilant in defending Odin as he slept, their weak minds simply weren't prepared for the day, when he didn't wake up. They weren't prepared for someone finding a way to take Odin's power. 
- —Loki
Appearances
Featured Characters:
Supporting Characters:
- Sif
- Valkyrie (Brunnhilde)
- Dwarves (First appearance)
- Eitri (First appearance)
- Light Elves (First appearance)
- Faradei (First appearance)
- Warriors Three
Antagonists:
- Loki (Loki Laufeyson)
- Hela (First appearance)
- Garm (First appearance)
- Rock Trolls
- Ulik (First appearance)
- Frost Giants
- Ymir (Final appearance)
- Dark Elves
- Asgardian Wolves
- Ogres
- Graviton (Franklin Hall) (Only in flashback) (Final appearance)
- Masters of Evil (Only in flashback)
- Enchantress (Amora) (Only in flashback)
- Baron Zemo (Heinrich Zemo) (Only in flashback)
- Wonder Man (Simon Williams) (Only in flashback)
- Abomination (Emil Blonsky) (Only in flashback)
- Crimson Dynamo (Ivan Vanko) (Only in flashback)
Other Characters:
- Balder the Brave
- Odin (Odin Borson)
- Howlers (Ghost, soul or spirit) (Final appearance)
- Dum Dum Dugan (Ghost, soul or spirit) (Final appearance)
- Izzy Cohen (Ghost, soul or spirit) (Final appearance)
- Rebel Ralston (Ghost, soul or spirit) (Final appearance)
- Sgt. Jack Fury (Ghost, soul or spirit) (Final appearance)
- Percy Pinkerton (Ghost, soul or spirit) (Final appearance)
- Dino Manelli (Ghost, soul or spirit) (Final appearance)
- Gabe Jones (Ghost, soul or spirit) (Final appearance)
- Frey (Mentioned)
Locations:
Items:
- Mjolnir
- Norn Stones (Mentioned)
- Casket of Ancient Winters
- Captain America's Uniform
- Captain America's Shield
- Hawkeye's Suit
- Hawkeye's Bow, Trick Arrows
- Panther Habit
- Vibranium Energy Daggers
- Ant-Man's Suit
- Wasp's Suit
- Bio-Synthetic Wings
- Bloodaxe (Enchanted Axe)
Vehicles:
Synopsis
Hawkeye regains consciousness in Alfheim where the light elves are fighting a desperate battle against Loki's forces, composed mainly of monstrous wolves. Loki himself keeps Thor imprisoned so that he can gloat about his master plan, which he set in motion all the way at the beginning of the series. It turns out, he was manipulating events all the way from Thor's initial confrontation with Odin, and even was behind The Breakout and The Masters of Evil. The whole point of all that scheming was so that he could gain control of the Odinforce, the source of Odin's power, and prevent the Allfather from waking up. With this power he was able to take over Asgard and has sent his armies to conquer the other realms, making Midgard irrelevant.
As for the other Avengers, they're not exactly in good spots. Ant Man and Wasp are transported to Jotunheim where they have to deal with frost giants (well, Ant Man at least. Jan was knocked out during transportation) In Niflheim, Captain America is confronted by the spirits of his dead comrades from the war, who urge him to give up and go to his hero's rest. Hulk gets to go to Vanaheim where the Vanir have been enslaved by trolls. Black Panther ends up in Svartalfheim, the old world of the dark elves, and gets chased by their restless spirits. Iron Man meanwhile wakes up in Nidavellir where he meets the king of the Dwarves, but they have problems of their own.
Each of the Avengers has to fight to overcome unique challenges throughout the realms, but they slowly but surely work their way forward. Hank protects Jan from the frost giants who are utilizing the previously stolen casket of ancient winters, but gets thrown off a cliff before being rescued by Sif and the Valkyries. Black Panther uses Vibranium to protect himself from the dark elves, and escapes through a magic well into another realm. Hulk gradually smashes his way through the trolls, rescuing the Warriors Three who resolve to retake Asgard with his help.
Cap at first seems ready to give up, but after wondering where Bucky is, thinks himself still alive, and resolves to keep fighting. He then demands that Hela let him out of Niflheim. Hawkeye is helped out by the light elf Faradei, a fellow archer. Running out of Arrows, they prepare to fight to the death, but are rescued by Black Panther. Faradei tells them that Alfeim is essentially lost, but they can still use a ship to get to safety.
Iron Man meanwhile fights a giant named Ulik with only one repulsor arm (the rest of the armor was lost in transit), and after hitting him with a blast from his arc reactor, escapes with the dwarf king to the forges of Nidavellir, where he asks, "Ever make a suit of armor? Thor meanwhile is still in Loki's clutches, and Loki promises that along with Baldur, he will face execution soon enough.Trivia
- Giant-Man actually says "I love you" to Wasp. However, she's unconscious and doesn't hear him, nor does she appear to know he said it afterwards.
- Tony Stark is saying his most famous quote of the MCU: "I am Iron Man."