What David Duchovny Is Really Like On Set, According To The Estate's Rosemarie DeWitt - Exclusive

Four cousins gather at what they think is the deathbed of their extremely wealthy aunt in the new black comedy "The Estate," but their reason for assembling is less than wholesome. None of them are there to pay their respects — several of them haven't seen the old lady in years — but all of them are there to smother the woman (played by screen legend Kathleen Turner) in kindness, in the hope that she might just break out her will and give them a little something extra, or even something at all.

While three of the cousins are played by Toni Collette, Anna Faris, and Rosemarie DeWitt with varying degrees of scheming, obsessiveness, and (in the case of Collette) a little bit of empathy, the fly in the ointment is cousin Richard, played with cringeworthy hilarity by David Duchovny. Not very bright, likely to say whatever flitters into his mind at any given moment, and possessed of an unhealthy attraction to Collette's Macey — his own cousin, mind you — Richard seems to have truly knocked a few screws loose.

Duchovny, of course, is used to playing off-kilter characters. From his breakthrough role as conspiracy-obsessed FBI agent Fox Mulder on "The X-Files" to the decadent writer Hank Moody on "Californication" to his satirical portrayals of himself on "The Larry Sanders Show" and "The Chair," Duchovny brings a slight glint of lunacy to everything he does.

Is he just as much a madman on the set when the camera isn't rolling? Does he stay in character, no matter how bizarre? That's the question Looper posed to his castmate Rosemarie DeWitt in our exclusive interview.

Rosemarie DeWitt says that even when playing a character as dim-witted and creepy as Richard in "The Estate," David Duchovny isn't one to keep the crazy going even when the cameras stop rolling.

"No, he's not," she explained. "He's a really smart guy, which I'm sure you could probably tell from his work. He's a writer and director and all these other things. I'm sometimes surprised that people can be as generous as they are. He helped me when we'd improv some things. He's like, 'Try one where you ...' Because I forget that he does direct and write. He was generous with that and supportive."

But DeWitt did add that Duchovny will often make himself laugh with his own antics on the set. "This might be where David is crazy," she revealed. "He breaks up at himself. He does something funny, and then he cracks himself up." From the sound of it, he's in good company: "We're all crazy," DeWitte said. "Every single actor on that set is a little crazy, but in a good way."

"The Estate" is now playing in select theaters.