Fox unveiled the first preview for its upcoming tentpole "X-Men: First Class." The prequel features an entirely new cast — James McAvoy, Michael Fassbender, and Nicholas Hoult– and director, Matthew Vaughn. It comes off like a superhero "Mad Men," what with the clips of President Kennedy and 1960s setting. Will the Beast knock back a few highballs and complain about those "damn beatniks" before trying to sleep with his secretary? We find out on June 3.