The casts of the original X-Men trilogy and 2011’s X-Men: First Class team up for May’s highly anticipated X-Men: Days of Future Past. “It’s not a reboot because there’s some of the same characters and same actors,” says Bryan Singer, who previously directed the 2000 original and 2003’s X2. “But it’s also not a conventional sequel—I call it an inbetweequel.”

Wolverine (Hugh Jackman) is sent back to the 1970s by future Professor X (Patrick Stewart) and Magneto (Ian McKellen) to stop a cataclysmic event. There, he must help young Xavier (James McAvoy) reunite with his foster sister, Raven (Jennifer Lawrence), and best pal, Erik/Magneto (Michael Fassbender). As Singer teases, “These are very big emotional stakes as well as, you know, cool giant robots and superpowers.”

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