X-Men: Days of Future Past succeeds at being a thrilling and fun superhero movie, balanced by well-earned dramatic weight.
X-Men: Days of Future Past imagines a near-future in which both mutants and humans have been decimated by deadly killing machines known as The Sentinels. In this nightmarish dystopia, Professor X and his “old friend” Magneto gather the most powerful surviving X-Men together for a last-ditch effort to stop the Sentinel war: altering the past so that it never happened in the first place.
That plan requires Kitty Pryde sending Wolverine’s consciousness back into his 1970s body, in order to stop an event that forever sets history on the course of a dark future. But things are bleak in the past, as well: young Charles Xavier, Magneto and Mystique are all damaged and estranged from one another; the events of the Cuban Missile Crisis (seen in X-Men: First Class) have already inspired the beginnings of the Sentinel program; and with every passing moment in the future, the Sentinels get closer to eliminating the last of the X-Men and destroying all hope of altering history.