Bombshell is a musical originally created in the context of the TV show Smash, in which it is written and performed by its main cast. It is a musical about the life of Marilyn Monroe.
In the real world, Marc Shaiman co-wrote the score with Scott Wittman. In universe, its book and lyrics are by the show characters Julia Houston and music by Tom Levitt, choreographer Derek Wills and its producer Eileen Rand.
A soundtrack featuring the music from the musical was released in 2013. The songs were featured in a one-night charity concert, and the musical is being adapted to a real stage musical on Broadway.