While filming The Disaster Artist — the comedy about the making of the infamously terrible 2003 movie, The Room — star and director James Franco stayed in character as Tommy Wiseau for the entirety of the shoot.

For the uninitiated, Wiseau has a distractingly eccentric personality, shoulder-length black hair, a vaguely Eastern European affectation and a style of dress akin to the frontman in an AC/DC cover band.

“I couldn’t deal with it, straight up, for the first two days,” remembers co-star and producer Seth Rogen. “People would come up and ask me, ‘Where’s James?’ And I was always like, ‘He’s right fucking there!'”

Franco and Rogen, along with co-star Dave Franco, spoke after a packed Saturday night screening at the DGA. The Disaster Artist, which is set to be released by A24 on Dec. 1, first premiered to rave reviews in March at SXSW before screening last month at the Toronto International Film Festival. Now, the comedy about one of the notoriously worst movies ever made is gaining early awards buzz.

“My grandmother came out and she just did not get what the fuck was happening,” Rogen said. “She was walking around like, ‘I thought James was in the movie?’ I never explained it to her.”

But James Franco was not Wiseau’s first choice to portray him in the movie.

“I was his second choice,” Franco said. The first choice? “He wanted Johnny Depp.”

When asked about how he came to understand Wiseau as a character, Franco said, “I think Tommy really thinks he is James Dean.”

Franco played the legendary actor in Mark Rydell’s 2001 telepic James Dean and said his preparation to play Dean was the same process he employed to play Wiseau — he would watch their work, religiously.

Added Franco, “But The Room is a little different than East of Eden.”

Sources