But it's not an act.
"The first time I saw him he was covered in paint and reading a book and then I was like, 'OK, I get it. You paint and read,'" stand-up comedian Rogen, 32, told ABC News in a new interview. "Now like it’s been almost twenty years; it’s not a shtick. No one pretends to read and paint for twenty years. He’s actually painting and reading."
The feeling is mutual. Calling Rogen "one of my closest friends," Franco, 36, added that the relationship has changed him, and the way he views his career.
"I was taking myself too seriously on films,” Franco said. “I needed a different place and school had a different set of rewards and had a different goal and once I did that it took so much pressure off the movies."
Now, they're doing even more movies together. Rogen and Franco are currently putting the finishing touches on a new film, "The Interview," about two journalists asked to kill North Korean leader Kim Jong-un.
But it's not the only project for Rogen, who also testified before Congress in February about Alzheimer's, a disease that has affected his mother-in-law. To his dismay, only a handful of officials showed up to hear his heartfelt testimony.
"I was a little mad and disenchanted," the actor said of the experience. "They set up a system for these public hearings and none of the people who are supposed to vote attend them. ... They’re defended for not doing their job."