EXCLUSIVE: Tom Papa has joined the cast of Behind The Candelabra. The former Marriage Ref host will play Liberace’s long time pal Ray Arnett in the Steven Soderbergh-directed film. Michael Douglas plays the flamboyant piano man, who died in 1987, in the HBO Films project. Jerry Weintraub is producing. The film, which will debut on HBO, is set to start shooting in LA next month. Also in Liberaceland, Dan Aykroyd is in Behind The Candelabra, playing manager Seymour Heller. Matt Damon has been cast as the entertainer’s partner Scott Thorson. Papa is repped by ICM Partners and managed by 3Arts Entertainment.

Deadline's Dominic Patten - tip him here.