Tony winners John Rubinstein and Linda Lavin have joined the cast of Being the Ricardos, the upcoming movie following a week in production of the hit sitcom I Love Lucy. As of yet, it’s unclear what roles the stars will be playing, but Amazon Studios confirmed March 29 that filming had already begun.

The film, directed and written by Tony nominee Aaron Sorkin (To Kill a Mockingbird), stars Nicole Kidman and Javier Bardem as Lucille Ball and Desi Arnaz, respectively. They’re joined by Tony winner Nina Arianda (Venus in Fur) as Vivian Vance and J.K. Simmons as William Frawley, who played Ethel and Fred on I Love Lucy.

Being the Ricardos follows the show’s cast as they go from table read through audience filming for a single episode. As the countdown to taping begins, Lucy and Desi face a crisis that could end their careers and another that could end their marriage.

Also joining the company is Tony Hale as I Love Lucy executive producer and head writer Jess Oppenheimer, along with Jake Lacy and Alia Shawkat as the show’s longtime writing partners, Bob Carroll, Jr. and Madelyn Pugh. Also featured in the cast with roles to be announced are Clark Gregg, Nelson Franklin, Robert Pine, and Christopher Denham.

“My brother Desi and I signed on because this is a story of our folk’s real-life passionate, tempestuous and complicated relationship and not a recreation of I Love Lucy—no one could do that,” says executive producer Lucie Arnaz. “We felt exploring that relationship could be an enlightening challenge.”

Escape Artists’ Todd Black, Jason Blumenthal and Steve Tisch are producing with executive producers Jenna Block, David Bloomfield of Escape Artists, Stuart Besser, Lucie Arnaz, Desi Arnaz, Jr., and Lauren Lohman.

The creative team includes director of photography Jeff Cronenweth, production designer Jon Hutman, costume designer Susan Lyall, set decorator Ellen Brill, sound mixer Steven Morrow, and editor Alan Baumgarten.