(Photo: Kevin Winter/Getty Images

Billy Bob Thornton is set to play a guy who may—or may not—exist, with Deadline reporting that the Bad Santa star has signed on to appear in an upcoming adaptation of James Frey’s memoir/novel/Oprah provoker A Million Little Pieces. Thornton will play Leonard, the mysterious mafia boss/mentor who looked after Frey during rehab, maybe. (This particular book makes definitive statements like that pretty tricky to stand behind.)

The film is being written by married film-making team Aaron Taylor-Johnson and Sam Taylor-Johnson, with Sam set to direct and Aaron—whose other notable credits include the Kick-Ass movies—starring as Frey. They’ll be joined by Charlie Hunnam and Blade Runner 2049's Carla Juri, both announced today, as well as a previously cast Giovanni Ribisi.

Frey’s “memoir” became a bestseller in 2005, when Oprah Winfrey picked it as a selection for her all-powerful book club. Things fell apart, though, when journalists began looking into the detail’s of Frey’s battle with addiction, eventually discovering that he’d fabricated most of them. In the meantime, the author had already written a second book about Leonard, meaning that Thornton will actually have twice as much material to draw on—or not—when he sets himself to the task of portraying the Schroedinger’s Mobster he’s now agreed to play.