Hollywood maverick James Franco co-stars with his younger brother Dave in The Disaster Artist, a new passion project which tells the true story of how "the greatest bad movie ever" came into being. 

In the film, James plays failed actor Tommy Wiseau who teams up with friend and fellow flop thespian Greg Sestero (Dave Franco) to make The Room, a film drama so very, very bad that it went on to attain cult status among Hollywood insiders and movie fans. 

Watch our full interview with Dave and James Franco 

This is the first time the Franco brothers have appeared together in a movie. Dave, who has starred in TV show BoJack Horseman and may be set for a breakthrough with his upcoming portrayal of doomed Hollywood idol Montgomery Clift in a new biopic Zeroville, told RTÉ Entertainment that working with his older brother was a pleasure. 

"It was great, it was great. This is the first time we've worked together in a substantial way and we get along really well, we do," he said.

Read our review of The Disaster Artist

"A lot of people are trying to ask "what didn't work, what were the negatives of working with your brother . . . ?" but there really weren't any. We have very similar sensibilities, he's a great actor's director, he obviously understands the psyche of an actor, and he really values everyone's opinions on set."

Dave and James Franco in a scene from The Disaster Artist 

James, who takes meta acting to a whole new level as Tommy Wiseau, spoke about his feelings when he first saw The Room, the bungling future cult classic. "I came to the movie after I read the book so I knew the backstory and the backstory is so moving, that book is incredible.

James Franco as Tommy Wiseau in The Disaster Artist

"What could have been a book poking fun at all the mistakes these guys made when they were making this movie was actually a touching story about friendship and persevering in the face of rejection so when I finally watched the actual movie The Room it was bad in all the best ways but I was actually very moved by it because I knew how much it meant to those guys when they were making it."

"So having these two things - the wacky story behind it and the moving story about making it - were incredible ingredients for a movie."

Alan Corr @corralan

The Disaster Artist is in cinemas on December 8.