So Gone Girl is a very serious thriller, which may be less serious once you know he pulls his penis out for the movie. I think this was an uber smooth move on his part because lately no one can interview him without asking his opinion on the fact that he's going to be in the new Batman movie, how do you change the internet's focus - celebrity nudity.
His thoughts in an MTV interview:
“It’s ironic, because David [Fincher] said to me from the beginning, this is a warts and all movie. It can have no vanity. You have to see the naked underbelly of this character,” Affleck continued. And yes, when he says “naked underbelly,” he means it literally as well as figuratively.
“There’s some brief, ah, very brief nudity, I think,” Affleck hedged. But when reminded that people might well be going to see “Gone Girl” for literally no other reason than to get a glimpse of his wang, he capitulated.
“The penis is in there!” Affleck said. “It’s IMAX penis! You’ve gotta pay fifteen bucks to see it in 3D… it’s better in 3D.”