Thanks to a time travel story, “X-Men: Days of Future Past” puts right what “X-Men: The Last Stand” once made oh-so wrong, to paraphrase “Quantum Leap’s” tagline. For the uninitiated, “X-Men’s” unique film history began in 2000 when the first film premiered, eventually resulting in an industry standard. Superhero fans owe director Bryan Singer (“The Usual Suspects”) a great deal of gratitude for igniting the caped flame that remains lit every summer –– not to mention his reverential treatment of the source material.

Beast/Hank McCoy (Nicholas Hoult), young Charles (James McAvoy) and Wolverine/Logan (Hugh Jackman) appear in a scene set in the 1970s in “X-Men: Days of Future Past” . (photo courtesy of Fox Pictures)

Sadly, a tiff with Fox Pictures ended in Singer’s exodus (forced as it was) from the third film. What followed was one of the most disappointing third installments in franchise movie history (I’m not exaggerating, and I’m not alone). “Last Stand” wrote out most of the main cast, killed off a couple and left the survivors to do little else but follow MacBeth down the road only traveled by the pridefully blind. It almost killed the franchise; I’m talking “Batman and Robin” killed. But hope arose after a predictably mundane Wolverine origin story in “X-Men: First Class” that reunited the team when young idealists Charles Xavier (James McAvoy) and Erik Lehnsherr (Michael Fassbender) first met. Hope returned. And along with that hope, Singer patched things up with Fox and produced the film.

We now come to “Days of Future Past”. Back in the directing chair, Singer creates the sequel to “X2” we all needed eight years ago. But rather than abandon the marvelous performers of “First Class” in the past or the others he nurtured in the “not too distance future,” as the films always began, he combines them in a time-travel story –– one that undoes everything “X-Men” lovers loathed about so many story elements post-“X2”.

Remember the 1992 “X-Men” cartoon? Those enormous robots, the Sentinels, that can target mutants based on their DNA? More than 20 years later, visual effects are ready to bring these uncanny spectacles to life in the best “X-Men” film to date. In a dystopian future, the world has become a desolate place. Mutants live in hiding, and the X-Men’s numbers have dwindled to near single digits. A small group, lead by originals Shadowcat (Ellen Page) and Iceman (Shawn Ashmore) outwit the bots by continually sending fellow mutant Bishop’s (Omar Sy) consciousness back in time to warn them.

But the game changes when X-Man himself, Professor X (Patrick Stewart), arrives along with Wolverine (Hugh Jackman), Storm (Halle Berry) and Magneto (Ian McKellen), and is forced to patch things up with his “frenemy” Charles, lest all mutantkind meet a brutal end.

Using her special time-phasing ability, Shadowcat sends Wolverine’s consciousness back to a pivotal moment in history — the end of the Vietnam War — when young Mystique (Jennifer Lawrence) kills weapons designer Dr. Bolivar Trask (Peter Dinklage), setting in motion events that would lead to the implementation of the Sentinel program. Considering the tensions among Charles, Erik and Raven (Mystique’s born name), our clawed friend has his work cut out for him, especially since he’s on the clock as the mutants in the future make their real last stand to give Logan the time he needs.

Professor X and Magneto (both old and young), Bishop, Mystique, Iceman, Warpath (Booboo Stewart), Sunspot (Adan Canto), Blink (Fan Bingbing), Colossus (Daniel Cudmore), Rogue, Storm, Wolvey, Beast (Nicholas Hoult), Havok (Lucas Till), Quicksilver (Evan Peters), Toad (Evan Jonigkeit) and Ink (Gregg Lowe), along with a young William Stryker (Josh Helman) and a few familiar faces … are you exhausted by that list? The sheer size of the cast would make any reasonable viewer fear that cameos might backseat the story, but Singer and screenwriter Simon Kinberg know how to do it all. No need for backstory; everything just starts. Want know how Professor X is alive in the future when he died, or how Magneto got his powers back? Both are hinted at in “Last Stand”, and Kinberg’s script concerns itself with other more interesting endeavors. The story briskly moves, stopping just long enough for introspective moments and the occasional action sequence –– though this is more about how it will all end, not epic action sequences.

There’s even time to meet some memorable new faces. Surprisingly funny Evan Peter’s Quicksilver is one highlight, along with Blink’s awesome ability to bend space. And finally, an “X-Men” film that understands Storm’s powerset. But for all it’s grandiosity, “X-Men: Days of Future Past” most succeeds at presenting stellar performances and an intricate plotline. May more superheroes explore such sci-fi worlds as corrupt futures in need of correction. This is the finest X-film to date, as it breathes new life into a franchise that seemed to be nearing the bottom of the drain.