For questions about the X-Men: Days of Future Past, the seventh film in the X-Men Cinematic Universe, directed by Bryan Singer and largely based on the original comic book arc. Always use in conjunction with the [marvel] and [x-men-cinematic-universe] tags.
In the future, mutant hunting Sentinels have all but eradicated the mutant race and laid waste to the entire planet. The remains of the X-Men devise a plan to send the consciousness of one of the surviving X-Men into the past to thwart an assassination attempt which will change the course of history.
In the original comic story, Katherine "Kitty" Pryde is sent back. In the 2014 film, James "Wolverine" Howlett is sent back.
In addition to the feature film, the basic premise and story of Days of Future Past has been loosely adapted in episodes of both X-Men: The Animated Series and the Wolverine & The X-Men TV shows.