Teeth-grinding adrenaline-pumping low-cognition guy movie. The three prior X-Men movies alluded to the mysterious amnesic history of the unsophisticated yet compelling character Wolverine; this story at long last unfolds his 175-year lifespan - and why that one nasty badguy is so keen on almost but not quite killing him.
Understand that this movie is a tangent to the obsessively complex X-Men comic book series. Lots of characters are introduced, many with very brief involvements featuring unexplained extreme behavior which will leave fanboys smiling and nodding while their SOs tilt their heads wondering "what the heck was THAT all about?" Relax, enjoy, and recognize this is just a small part of a much bigger story.