Hugh Jackman as James "Logan" Howlett/Wolverine - Ralph Fiennes as Professor Charles Xavier - Daniel Day Lewis as Erik Lensherr/Magneto - Rose Byrne as Dr. Moira Mactaggert - Chris Pine as Scott Summers/Cyclops - Anna Kendrick as Jean Grey - Jamie Bell as Robert "Bobby" Drake/Iceman - Naomie Harris as Ororo Munroe/Storm - Joel Edgerton as Henry "Hank" McCoy - Matt Bomer as Remy LaBeau/Gambit - Gemma Arterton as Anna Marie/Rogue - Owain Yeoman as Piotr "Peter" Rasputin/Colossus - Michelle Trachtenberg as Katherine "Kitty" Pryde/Shadow Cat - Tony Curran as Sean Cassidy/Banshee - Ethan Suplee as Fred Dukes/The Blob - David Thewlis as Jason Wyngarde/Mastermind - Katheryn Winnick as Emma Frost - Riley Smith as John Allerdyce/Pyro - Nathan Jones as Cain Marko/Juggernaut - Peter Dinklage as Bolivar Trask/Nimrod -
A man called Weapon X is being experimented on in an a private facility. He is erased of all his memories, and has three indestructible adamantium claws from his knuckles, as well as an advanced healing factor. Confused and violent, he escapes the facility and runs off into the snowy forest of the Northern Canadian territory, into Logan County where he runs into a tribe of natives. He is violent to them at first, but a women sees that he is simply a scared and hurt, she manages to also convince the tribe to accept him, as he is a "gift from a spirits" and they should not ignore him.
Six years later, going by the name "Logan" now (based off of the county), he still doesn't know anything about the people who took him or his past before that. He now serves his tribe and has the woman who saved him (named Kayla Silverfox) as his paramour. He hunts with the wild animals and brings them foods as well as timber. It's a peaceful life for Logan, who ends up taking a rite of passage in the tribe. Where he finds out what animal "exists" in his soul. Like Kayla before him, who was a Silver Fox, Logan was chosen to prove his valor by fighting the best hunter in their tribe. As the two fight, Logan easily defeats him. With his ferocity and rage in battle, as well as claws and healing, the chief declares him The Wolverine! He tells Logan a saying he remembers, "It is not the size of the wolf in the fight, but rather the fight in the wolf".
Meanwhile, above someone is watching the tribe, especially the Wolverine.
In the Department H facility, a man named James MacDonald Hudson, and his wife Heather Hudson were called in to investigate and stop the terrorist William Stryker, who has is a radical Anti-Mutant activist, and believes that all of them need to be controlled and regulated by heavy enforcement, similar to how Hitler acted in World War II. Stryker's insane proposals were obviously rejected by Department H and the Canadian government, but he did have a cult following and privately funded his own facility to commit these terrible actions. James and Heather served Department H before as members of Alpha Flight, Guardian and Vindicator respectively. But retired after believing they had destroyed Stryker's facility. It was found out that an experiment of Stryker's, Weapon X, had actually escaped and been insufficiently brainwashed living in the Northwest Territory. If they could find him and possibly find out what he can do, or better yet what he knows, they could finally stop this madman from ruining anymore lives. They agree to take up the task and find this man.
Back at the camp, Logan and Kayla are celebrating his animal ceremony and enjoying themselves. The two eventually sneak off into the woods where they talk about what happened and how Logan never properly thanked her for all she and the tribe had done for him, right before he is about to say he "loves her", they hear something moving in the trees. Suddenly, screams and slashes can be heard as the camp gets raided. As Logan and Kayla come to the camp, he tries to use his claws to defend the camp. The person attacking it, is a tall blonde furious man with animal claws, who can heal similar to Logan. The two fight Wolverine eventually being overpowered and beaten into submission. As Wolverine wakes up, he sees the entire camp destroyed, all the people slaughtered, including who he believes to be Kayla. He screams at the sky in agony over this, and vows to destroy the man who committed these terrible acts, called Sabertooth.
A truck is driving through the Northwest Territory, not too far by and enters a secret facility. Out of the truck comes a man named David North, nicknamed "Maverick" who works for Stryker. He goes into the facility and into the office of William Stryker, who asks him how the displacing of Weapon X has gone, and he says successfully, that they were able to lure Sabertooth into destroying them. But that Department H and Alpha Flight probably know about him now and might try to stop them, Stryker says to let them try and if they become an issue, to take care of it.
In a bar Logan is drinking his troubles away, while Guardian and Vindicator enter and sit next to him. They explain who they are and how they believe the people who experimented on him can be stopped, since they've re-surfaced after all these years, once Wolverine was re-discovered. He says how a man, with similar claws and other powers to him destroyed his village and the women he loves, which they explain to probably another Weapon X subject, named Sabertooth. Wolverine says if they go to destroy Weapon X and William Stryker, they need to also find and destroy Sabertooth. They say it's a deal and walk out of the bar.
The three go to the Department H facility in Ottawa and equip Logan with his own costume (The Classic Yellow Blue Wolverine Costume) which at first he dismisses, but supports and warms up to because of its armored padding and flexibility. They know Stryker has smaller outposts around the Northern Canadian territories and they all go out to one in Nunavut. While there Wolverine, Guardian and Vindicator raid the base, trying to find any documents for the official location of the Weapon X headquarters where William Stryker would most likely be located. They can find it, but after being confronted by Maverick. After a large battle, he manages to knock out Guardian and Vindicator while Wolverine (because of his healing factor) manages to hold his ground.
Wolverine uses the information to return to the base in which his terrible experiments occurred, after he fights his way inside suffers extreme PTSD, having flashbacks of all he went through to get just powers and abilities. Inside he frees Guardian and Vindicator and they try to find Stryker and end all this, only to be confronted by Silver-Fox. Who was secretly a spy for Weapon X meant to trick Wolverine and control him, William Stryker announces that they learned so much about him in that captivity. Wolverine hurt by this betrayal goes after Silver-Fox, before being attacked by Sabertooth again. Wolverine attacks Sabertooth, who said he was also there to destroy the facility. After a long hard fight, Wolverine finally wins and asks Sabertooth why he destroyed the village and keeps attacking him, despite their similar goals. Sabertooth only said that they were born to be rivals, Wolverine lets him and goes after Stryker. He beats him and holds him to the snow. Stryker explains how Wolverine was "always an animal" and that he only improved him and gave him a purpose, and that if he only knew the creature he once was, he would actually be thanking him for erasing his memory. Wolverine punches Stryker and, also finds out the Alkali Lake dam was flooding the area, Wolverine leaves Sabertooth, Silver-Fox and Stryker there while escaping with Guardian and Vindicator.
After they leave, in Ottawa Wolverine says how he's not interested in working for the Canadian Government. He's a lone wolf, and plans to stay that way, now that his demons have been confronted he can explore the world, hopefully make a better man of himself than he once was, with new memories and adventures. James and Heather wish him farewell as he rides off into the distance. They than remember he took the suit.
After the credits... at Alkali Lake beach, something is seen walking up out of the water, the camera doesn't show it's face as it struggles to get a mask on. Revealing himself to be Deadpool, who looks right at the camera and speaks "You didn't think there would be a Wolverine movie without me, did ya!?"