Sarah Silverman has joined the cast of the forthcoming Leonard Bernstein biopic Maestro, alongside the previously announced Bradley Cooper, Carey Mulligan, Matt Bomer, and Maya Hawke. See photos of Cooper and Mulligan's on-set transformations here. As reported by Deadline, Silverman will take on the role of Bernstein's sister.

Silverman recently ventured into the theatre world, following her extensive film, television, and stand-up career (which included starring in the movie adaptation of RENT) with the release of her new musical The Bedwetter, currently in a world premiere run at Off-Broadway's Atlantic Theater Company. The show is based on the Emmy winner's bestselling memoir of the same name and features a book by Drama Desk winner Joshua Harmon and Silverman, with lyrics by Silverman and Emmy winner Adam Schlesinger, who also composed the music.

Maestro features direction by Cooper, who co-wrote the script with Oscar winner Josh Singer. The movie focuses on the love story of Leonard Bernstein and Felicia Montealegre Cohn Bernstein, which spans over 30 years – from the time they met in 1946 at a party and continuing through two engagements, a 25 year marriage, and three children.

The couple had three children together—Jamie, Alexander, and Nina—who worked closely with Cooper to develop the project. The biopic is Cooper's follow-up to his directorial debut, A Star is Born, which he also starred in opposite Lady Gaga.

In addition to being a celebrated concert conductor and composer, Bernstein wrote several musical theatre scores for Broadway, including On the Town, Peter Pan, Wonderful Town, Candide, and West Side Story.

A release date for the film has not been announced.