Melissa Leo and Sebastian Stan have joined Showtime's upcoming comedy "I'm Dying Up Here". The series is executive produced by Jim Carrey and Dave Flebotte, who is also the writer of the show. Clark Duke ("Hot Tub Time Machine") is also joining the cast as a regular.

Melissa will play the role of Goldie, a brassy comedy club owner who rules over her business with an iron fist and nurtures her comedians with tough love. Sebastian will play the recurring role of Clay, a funny, charming comedian on the rise, who declares irrelevancy as his biggest fear. Clark, meanwhile, will star as Larry, a ballsy young comedian from Boston who moves to L.A. with the hopes of making it big.

Previously announced cast members include Ari Graynor, RJ Cyler, Erik Griffin and Stephen Guarino.

"I'm Dying Up Here" is based on William Knoedelseder's non-fiction book of the same name. The pilot will be directed by Jonathan Levine. Also executive producing are Michael Aguilar and Christina Wayne for Endemol Shine Studios and Assembly Entertainment.