The first two “X-Men” movies were directed by Bryan Singer, who then wandered off for other projects and left the subsequent sequels and spin-offs to others. Now Singer’s back in X-mode, which could explain why “X-Men: Days of Future Past” marks a return to form for the Marvel Comics series.

Or maybe that’s just the time-travel talking. I am a sucker for a good old-fashioned warp in the time-space continuum, and “Days of Future Past” gives us a spirited one.

The movie opens in 2024, where the surviving X-Men (mutant humans with special powers) are being attacked by giant shape-shifting hunters called Sentinels. Thanks to the powers of Kitty (Ellen Page), a gray-haired Wolverine (Hugh Jackman) is sent back in time to 1973.

His mission is to stave off the invention of the Sentinels and the beginning of the great war between humans and mutants. He’ll try to stop Mystique (Jennifer Lawrence) from performing a decisive, history-altering act.

Strange — if the mutants can send somebody back in time and tweak history, why didn’t somebody think of this years earlier? We could’ve saved a lot of fuss.

The timeline allows for the ‘73-vintage Professor Xavier (James McAvoy) and Magneto (Michael Fassbender) — both actors were introduced in the 2011 prequel “First Class” — to appear in the same film as their mature selves, played by Patrick Stewart and Ian McKellen. It is very pleasant to see them all.

And whatever the logical problems with the story line, it’s clean enough to allow for an enjoyable, straightforward action picture. Everybody gets just the right number of one-liners and philosophical asides to provide ballast to the comic-book characters.

Mind you, it’s a little disconcerting to see President Nixon talking about mutants. And the film’s got a few new wrinkles to propose about the JFK assassination (some of the theories were trotted out in a pre-release publicity campaign).

Cameos abound for characters from the previous movies, some of which ought to remain surprises. Among the newcomers, Evan Peters makes an impression as Quicksilver, and Peter Dinklage takes a break from “Game of Thrones” to play an imperious scientist.

How “Days” fits into the chronology of the other “X-Men” movies is something for a million message boards to sort out. As for the 3-D spectacle, the movie really doesn’t do much with it, so you won’t be missing anything if you see it in a mere two dimensions.

Stay through the end credits if you’re a diehard fanboy or fangirl. A brief teaser at the close of this film’s 131 minutes points the way toward a sequel announced for 2016. So let’s mark our calendars, and hope that installment is as much fun as this one.

“X-Men: Days of Future Past” (3 stars)

A fun outing for the Marvel Comics franchise, as director Bryan Singer returns to duty and the saga’s timeline gets a major re-boot. Wolverine (Hugh Jackman) travels back in time to 1973, in order to stave off Mystique (Jennifer Lawrence) and a decisive historic event. Significant cast members reunite, and there’s a good blend of humor, philosophy, and action here.

Rating: PG-13, for violence

Opens: Friday at Alderwood, Cinebarre Mountlake Terrace, Everett Stadium, Galaxy Monroe, Marysville, Stanwood Cinemas, Pacific Place, Thorton Place Stadium, Woodinville, Blue Fox Drive-In, Cascade Mall, Oak Harbor Plaza.