Cash's television appearances include Brotherhood, Law & Order, Law & Order: Special Victims Unit, Law and Order: Criminal Intent, Mercy, and The Newsroom. Cash was also a series regular in the 2011 Fox comedy Traffic Light, which ran for one season. She currently stars in the FX Network series You're the Worst as Gretchen Cutler. She received critical acclaim for her performance, with the website The A.V. Club calling her acting in the second season "the best TV performance of 2015".
Additionally, Cash has numerous Off-Broadway credits, and in 2014 starred in the world premiere of Zoe Kazan’s play Trudy And Max In Love.
Cash's film credits include The Oranges, Winter of Frozen Dreams, Off Jackson Avenue, Begin Again, The Bits In Between, and The Happy House. She had a small role as Janet, Jordan Belfort’s assistant in The Wolf of Wall Street.
