- X23-23 (Laura) (Only appearance)
- Caliban (Only appearance; dies)
- Charles Xavier (Only appearance; dies)
- Rey (Only appearance; dies)
- Alkali Corporation (Only appearance)
- Transigen Project (Only appearance)
- Reavers (Only appearance)
- Dr. Zander Rice (Only appearance; dies)
- X-24 (Only appearance; dies)
- Transigen Project (Only appearance)
- Gabriela Lopez (Only appearance; dies)
- X-Men (Only appearance; drawing)
- Transigen Experiments
- Maria (Only appearance)
- Dominic Petros (Named only)
- Christopher Bradley (Named only)
- Sauron (Karl Lykos) (Only appearance; drawing)
- Will Munson (Only appearance; dies)
- Kathryn Munson (Only appearance; dies)
- Nate Munson (Only appearance; dies)
- Jackson (Only appearance; dies)
- Carl (Only appearance; dies)
- Weapon X Project (Mentioned)
- Dr. Rice's Father (Mentioned) (Deceased)
Races and Species:
- Earth-17315 (First appearance)
- Earth (First appearance)
- United States of America (First appearance)
- Mexico (First appearance)
- Mexico City (First appearance)
- Canada (First appearance)
- Earth (First appearance)
- Adamantium (First appearance)
- Wolverine's Suit (Only appearance; drawing)
- X-Uniforms (Only appearance; drawing)
- Cyclops Visor (Only appearance; drawing)
- Logan's cars (Only appearance)
In the year 2029, mutants are on the brink of extinction due to a virus created by the Transigen Project. Logan, who has aged greatly because his healing factor has begun to falter and the adamantium within his body is now poisoning him, spends his days working as a chauffeur and hustling for prescription drugs in Texas. The film begins with Logan peacefully sleeping until he hears a couple of people trying to wrench his limousine's wheels away. They are revealed to be Mexican gangsters. Logan confronts them, however, one of his claws fails to come out completely, and although he is overwhelmed at first, his rage gets the best of him, and he then brutally murders the entire gang with ease. He is met by Donald Pierce, Transigen's cyborg Chief of Security, who offers him a deal. Logan is not interested, and angrily demands that Donald leave. He and mutant outcast Caliban live in an abandoned smelting plant across the border in Mexico, where they care for a senile Charles Xavier, who has inadvertently killed his X-Men in a seizure-induced psychic attack one year earlier, caused by a degenerative brain disorder. Logan also saves money since he wants to buy a "SunSerker" yacht with which he can escape with Charles to a better place.
Logan is approached by Gabriela, a nurse for Transigen, who asks him to escort her and an 11-year-old girl, Laura, to a place in North Dakota called "Eden". After reluctantly accepting the job, Logan discovers that Gabriela has been murdered. He, Xavier, and Laura narrowly escape from her killers— Donald Pierce and his cybernetically-enhanced enforcers, the Reavers—but Caliban is captured and tortured in order to force him to use his mutant powers to track them. Logan and Xavier learn through a video on Gabriela's phone that Transigen was breeding mutant children with DNA samples from several mutants, but upon completion of the "X-24" project, the children were to be put to death. Gabriela helped several children escape from the Transigen compound before smuggling Laura across the border. Furthermore, Laura is revealed to be Logan's "daughter", as she was bred with his DNA.
While staying in Oklahoma City, Logan develops skepticism over the location of Eden, as he discovers it being referenced in an X-Men comic book that Laura brought with her. The Reavers find their whereabouts, but Xavier suffers another seizure and freezes everyone at the hotel with a psychic blast, allowing Logan to kill them. Logan then injects Xavier with a suppressant before they leave the city, with the overall ordeal leaving hundreds injured and several dead, and is noted by the media as being similar to a prior incident in Westchester, New York. The trio is eventually given shelter by a local family, the Munsons, after helping them round up their horses during a highway incident. That night, while Logan is away with Will, the patriarch of the Munson family, Xavier is mortally wounded and the Munsons are killed by X-24, a feral younger clone of Logan without his own healing factor and a much weaker adamantium skeleton, who then shackles Laura and heads to the Reavers' van. Xavier dies after Logan carries him to his car.
Caliban steals two grenades and detonates them, killing himself and destroying the van. Logan and X-24 clash and the latter gains the upper hand. However, Will appears and impales X-24 in the forepart of a combine harvester with his car with whatever strength he has left before dropping dead, while Logan and Laura once again escape. After burying Xavier, Logan reluctantly allows Laura to drive the duo to Eden, while X-24 is given a serum to restore his strength.
Logan and Laura arrive at Eden, which is a safe haven run by Rictor and former Transigen test subjects. There, Logan learns that the children will make an eight mile journey across the forest to the Canadian border and entrusts Laura to them before departing on his own. However, when the children are located and captured by the Reavers, Logan uses a mutant serum given to him by Rictor to restore his healing factor which rapidly heals all his past scars and injuries. He then begins slaughtering the Reavers, but the serum quickly wears off before he meets Zander Rice, the head of the Transigen project, who reveals that he engineered the virus to wipe out the mutant population and exact revenge on Logan for killing his father during his escape from the Weapon X program. Logan kills Rice and confronts X-24 while the children kill the remaining Reavers before overwhelming Pierce and killing him with their powers.
This time Logan overpowers X-24 and the latter is slammed on by a heavily armored truck by one of the children's telekinetic powers, but when the clone notices that his creator Rice has been shot down, he effortlessly lifts up the truck, grabs Logan off-guard as the helpless old man keeps yelling at the children to leave for safety. X-24 then impales Logan through a tree and repeatedly stabs the latter but is killed when Laura shoots him in the back of the head with an adamantium bullet that Logan had kept with him for years ever since he was shot with the same bullet by Stryker. Fatally wounded, Logan recalls his memories and friendships, finally realizing what it feels like to loved and be with a family before dying peacefully in Laura's arms with his last words being "So this is what it feels like"... Laura and the children mourn his death, and later they bury him before continuing their journey across the border. As they all leave, Laura returns to Logan's grave, removes the cross, and places it on its side to create an X, honoring Logan as the last of the X-Men.
- Hugh Jackman as Logan and X-24
- Patrick Stewart as Professor Charles Xavier
- Dafne Keen as X-23 / Laura
- Boyd Holbrook as Donald Pierce
- Stephen Merchant as Caliban
- Richard E. Grant as Dr. Zander Rice
- Eriq La Salle as Will Munson
- Elise Neal as Kathryn Munson
- Elizabeth Rodriguez as Gabriela Lopez
- Quincy Fouse as Nate Munson
- Jason Genao as Rictor
- Lennie Loftin as Jackson
- Bryant Tardy as Bobby
Additionally, Rey Gallegos portrays Rey. Krzysztof Soszynski, Stephen Dunlevy, Daniel Bernhardt, Ryan Sturz, and David Kallaway appear as the Reavers Mohawk, Macon, Bone Breaker, Pretty Boy, and Danny Rhodes respectively. Hannah Westerfield, Ashlyn Casalegno, Alison Fernandez, Parker Lovein, Salef Celiz appear as Rebecca, Charlotte, Delilah, Lizard Boy, and Jonah repectively. Doris Morgado portrays Maria.
- There are no after-credits scenes in the theatrical release.
- A short film called Deadpool: No Good Deed was shown before the theatrical runs of this film.
- A black-and-white version of the film, titled Logan: Noir, had a one-night theatrical run in the United States on May 16, 2017. This version is also featured on the home video release of the film.
- While the film is intended to take place in the new timeline for the X-Men film universe that originated in X-Men: Days of Future Past, since its events develop in the future, it should be noted it instead takes place in yet a different reality, Earth-17315.
- The film's screenplay, written by Scott Frank, James Mangold, and Michael Green, was nominated for the Academy Award for Best Adapted Screenplay at the 90th Academy Awards. It is the first time a film based off Marvel Comics was nominated at the Academy Awards for screenwriting.
- Director James Mangold had an idea for a cameo for Sabretooth, to whom Logan would've gone for help when on the run in the gambling town. The idea wasn't developed beyond that, and it eventually didn't make it to the final script.
- Among the genetic donors for the X-23 children is Christopher Bradley, who previously appeared in X-Men Origins: Wolverine and was portrayed by Dominic Monaghan.
- The film was originally intended to open on the Westchester incident, and would clearly establish which of the X-Men were killed. However, this was dropped early in the process, particularly as it would potentially change the focus of the film.
- James Mangold has confirmed that the depiction of Logan's death in this film was an intentional callback to Yukio's premonition of his death in The Wolverine.
- One of the deleted scenes connects Logan with X-Men: The Last Stand: At the dinner table, Kathryn Munson asked if Logan was married. Xavier claims that Logan was married to Jean Grey, and that Logan also killed her (which he did in Last Stand).