Bryan Singer's first two X-Men movies are considered high-points of the superhero genre, combining strong characters, ripping action and deep layers of resonant subtext. Then he abandoned the franchise to make Superman Returns (2006), leaving mindless action-comedy filmmaker Brett Ratner to make the underwhelming X-Men: The Last Stand. Fans thought the characters were done forever. And the even less coherent X-Men Origins: Wolverine (2009) seemed like the final nail in the coffin.

X Men Days of Future PastNicholas Hoult, James McAvoy and Hugh Jackman in 'X-Men: Days of Future Past'

Then Matthew Vaughn stepped into the ring, hot off his post-modern superhero romp Kick-Ass (2010), he went back in time for X-Men: First Class (2011), a clever reworking of the characters that allowed him to recast them with rising-star actors like Michael Fassbender, James McAvoy, Jennifer Lawrence and Nicholas Hoult. Never one to hang around or repeat himself, Vaughn then left to work on his thriller The Secret Service, starring Colin Firth, Michael Caine and Samuel L. Jackson.

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So now Singer is back in the picture, returning to the franchise he launched with a time-hopping story that works as a sequel to both First Class and The Last Stand. The casts of both films share the screen this time, as the older X-men send Wolverine back in time to change history 50 years earlier in 1973.

The film has had a mixed response so far from critics, as the screen is over-crowded with characters and pointless action and yet still has a focus on characters and current global issues. Fans will of course love it and immediately start the countdown to the 2016 release of Apocalypse, the third film in the First Class trilogy. Its ancient villain can be glimpsed in the post-credit sequence at the very end of Days of Future Past.

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Patrick Stewart takes wife to world premiere of X-Men: Days of Future Past: