George Clooney speak out on behalf of gay marriage

George Clooney tells E!'s Marc Malkin that he'll be playing AFER attorney David Boies in the L.A. production of Dustin Lance Black's '8'.

Clooney's participation was announced in December, but until now it was unclear what role he would be playing.

Said Clooney to Malkin: "I think the world is changing and it's becoming less and less of an issue and I think it shouldn't be long now," Clooney said. "I think younger people are looking at this like, 'Who cares?' I do believe it's generational, much like the civil rights movement. Young people started taking to the streets and things changed. This really is the final leg of the civil rights movement."

Clooney told The Hollywood Reporter in December: “It is astonishing that gay and lesbian Americans are still treated as second-class citizens. I am confident that, very soon, the laws of this nation will reflect the basic truth that gay and lesbian people -- like all human beings -- are born equal in dignity and rights.”

'8' will run one night only at Los Angeles’ Wilshire Ebell Theatre on March 3.