Michael Fassbender, Hugh Jackman, and James McAvoy (or Magneto, Wolverine, and Professor X) apparently made the X-Men Days of Future Past set incredibly fun to be on.
"Michael is one of those actors you had to coax out of the trailer. He'll wait in there for hours and hours – he's very difficult, very ornery on set," Jackman joked. "So there was really only one song [that would get him to come out], and I used to get the sound guy to play it very loud in the studio as he came in, just so he could get his mojo up."
That song was Robin Thicke's "Blurred Lines."
Watch what happened next: