It’s back in the saddle again for Matt Damon and Ben Affleck, who have not appeared in a film together since the late ’90s. The two are starting work on a movie about Boston’s notorious gangster James “Whitey” Bulger.

Damon is slated to star as Bulger, while Affleck has been tapped to direct. The screenplay will be written by ‘The Sopranos’ and ‘Boardwalk Empire’ executive producer Terence Winter. No one is sure how the story will take shape, since Bulger’s life of crime spanned many decades, including 12 years on the FBI’s most wanted list, until he was arrested at age 81.

“It’s always a question of what part of the story do you tell, and biopics are always a little cumbersome,” said Damon. “We’re still figuring it out.”

Damon and Affleck grew up together in Boston, where they heard stories of Bulger’s life. The two won an Oscar for their screenplay for 1997′s ‘Good Will Hunting,’ another Boston-based film, and last appeared together in Kevin Smith’s ‘Dogma‘ in 1999. “Matt and I have been looking for something to do together for some time,” said Affleck of the project. “We’ve heard about Whitey Bulger since we were kids, and we are excited by the prospect of putting it on screen.”

More From 107-3 KISS-FM