Inside the issue - which is available for just £1.99 on your iPad - Singer revealed that he's not worried about the size of his cast, which includes the likes of Patrick Stewart, Hugh Jackman, Michael Fassbender, Jennifer Lawrence and many (many) more.
"I wanted a full cast," he tells TF, "but I didn't want it to feel forced. We wanted to make it feel organic, not take a 'kitchen sink' approach but bring together characters with interesting powers."
He adds: "The movie has a lot of humour at the beginning, then as the stakes grow, it gets darker and darker..."
X-Men: Days Of Future Past opens in UK cinemas on 22 May 2014.
For more from Singer, pick up the brand new issue of Total Film, which is out now, and includes an exclusive look at Divergent, The Raid 2, and Bad Neighbours as part of The Future 100, your ultimate movie preview. Plus get FOUR incredible free posters, too.
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