Gervais is resuming his role as Dr. McPhee in Night at the Museum 2, which is scheduled for release in 2009. He originally took the part as payback to Stiller, who did a laugh-out-loud spoof of himself in one of Extras' most memorable episodes.

"He has sent me an e-mail saying, 'So I'm doing this film and we've written a part for you. Do you want to return the favour? No pressure,'" says Gervais. "So now I'm back for two."

And he's glad to be back. Gervais is coming off what he described as one of his most memorable days ever on set.

"Not only did I meet Robin Williams, who I didn't get to see last time . . . but I met Crystal the monkey. Amazing, it was the best day ever."

Though Gervais didn't get to work with Williams on the first movie, the legendary comedian sent him a gift after the first film wrapped: A scrapbook enclosed with a note reading, "I'm so sorry I didn't get to work with you." Gervais was blown away by the gesture -- as well as by Williams' stamina on the set.

"I think [Williams] must just go home and collapse because there is no off switch. He's just funny all the time. You say something, he does a sketch with voices and that. It's just amazing. I just sat there watching him. He's incredible."