VIDEO: James McAvoy, Patrick Stewart Talk 'X-MEN' on GMA

James McAvoy and Patrick Stewart will play the younger and older versions of Professor Xavier in the highly anticipated film X-MEN: DAYS OF FUTURE PAST. Today the actors stopped by ABC's Good Morning America to talk about their shared role in the film.

"I watch everything that Patrick has ever done, starting with the earliest things I can find on YouTube," McAvoy said of preparation to take on a younger version of Stewart, who responded, "I never looked this good. So I thought maybe people would remember me that I looked like James McAvoy."

Check out the appearance below!

Bryan Singer's X-MEN DAYS OF FUTURE PAST hits theaters on May 23rd. Get a First Look below! the film stars Patrick Stewart, Ian McKellen, Hugh Jackman, Michael Fassbender,James McAvoy, Jennifer Lawrence, Halley Berry, Nicholas Hoult, Ellen Page, Shawn Ashmore, Peter Dinklage, Omar Sy, Daniel Cudmore, Fan Bingbing, Boo Boo Stewart, Adan Canto, Evan Peters, Josh Helman, Lucas Till and Evan Jonigkeit.

The ultimate X-Men ensemble fights a war for the survival of the species across two time periods in X-Men: Days of Future Past. The beloved characters from the original "X-Men" film trilogy join forces with their younger selves from X-Men: First Class, in an epic battle that must change The Past - to save our future.

VIDEO: James McAvoy, Patrick Stewart Talk 'X-MEN' on GMA