Incoherent tangle — It should deliver the best of both X-Men worlds but Days of Future Past lacks the X-Factor

X-MEN Days of Future Past: This joint venture for two major Marvel movie stablemates should be delivering the best of both X-Men worlds, but at times it’s a total drag.

THE action blockbuster X-Men: Days Of Future Past starts out fast, furious and funky — let’s go to the 1970s, everyone! — before fizzling out to a forced, flat effort.

This joint venture for two major Marvel movie stablemates should be delivering the best of both X-Men worlds.

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News_Image_File: Hugh Jackman is never better in the role of Logan/Wolverine.

After all, there’s plenty of unfinished business on the original side of the X-Men fence where Mutant main man Professor X (Patrick Stewart) and his lifelong frenemy Magneto (Ian McKellen) still reign supreme.

As for their younger alter egos, Charles Xavier (James McAvoy) and Erik Lehnsherr (Michael Fassbender), that pair deserved another chance to do their thing after getting off to such a solid start in the hit 2011 reboot X-Men: First Class.

News_Image_File: James McAvoy and Patrick Stewart in X-Men: Days of Future Past.

Unfortunately, after initially running hot with breathtaking 3D effects and a fascinating premise, Days Of Future Past gradually cools into an unnecessarily convoluted, compromised product.

An exciting prologue staged in the present sees the Mutants on the brink of extinction at the hands of those ruthless robotic exterminators, the Sentinels.

In a desperate bid to save the day, Wolverine (Hugh Jackman) is sent back to Watergate-era Washington to change the course of history that led to the rise of the Sentinels.

The Prof and Magneto instruct Wolvie to look up Charles and Erik while he’s there, or otherwise the odds of his near-impossible mission will just continue to rise.

News_Rich_Media: Dinklage admires Jackman

Does Wolverine need it any tougher? His fellow Mutant Raven (aka Mystique, played by Jennifer Lawrence) thinks so.

If she goes ahead with the 1973 assassination of a leading genetic scientist (Game Of Thrones star Peter Dinklage), then all hope is lost.

By the halfway mark of Days Of Future Past, this straightforwardly intriguing storyline gets caught up in an incoherent tangle from which it can never properly free itself.

The ’70s stuff certainly keeps up its part of the bargain. Jackman (never better in the role of Logan/Wolverine), McAvoy, Fassbender and Lawrence work together incredibly well.

News_Image_File: Michael Fassbender, pictured, and co-stars Jackman, MCAvoy and Lawrence work together well.

And when the quartet is temporarily blown off-screen by the long-awaited arrival of super-fast slacker Quicksilver (Evan Peters), the film becomes a real blast.

Shame he couldn’t have stuck around longer. You’ll miss Quicksilver big-time whenever director Bryan Singer crosses back to the future, where the likes of Storm (Halle Berry) and Kitty Pryde (Ellen Page) pull some faces while the Sentinels pull their triggers on a bunch of lesser Mutants.

These sequences play like out-takes from other inferior outings, and are a total drag for the most part.

News_Image_File: Game of Thrones star Peter Dinklage plays a leading genetic scientist.

On an overall basis, the meshing of two eras and two X-Men casts gives Days Of Future Past a stop-start rhythm that makes the later stretches of the story too hard to follow.

While there are some astonishing action sequences — such as when Magneto drops a massive football stadium on the White House — there are also some major plot wrinkles that are just never satisfactorily ironed out.

X-MEN: DAYS OF FUTURE PAST (M)

Director: Bryan Singer (X-Men: X2)

Starring: Hugh Jackman, James McAvoy, Michael Fassbender, Jennifer Lawrence, Patrick Stewart, Ian McKellen

Verdict: Two-and-a-half stars. Many are called, few have the X-Factor

News_Image_File: Nicholas Hoult in X-Men: Days of Future Past.