Sarah Greene is an Irish actress and singer. Sarah became interested in acting when she saw Red Riding Hood along with her parents at the Opera House in Cork. A short time later she joined the CADA Performing Arts in Cork, where she took part in theatre plays and musicals until she was 19 years old. After leaving CADA Performing Arts she was trained at the Gaiety School of Acting in Dublin, from which she graduated in 2006.
She appeared with Daniel Radcliffe in the theatre play The Cripple of Inishmaan. For her performance as Helen McCormick she was nominated for the Tony Award and the Laurence Olivier Award as best actor in a supporting role. In 2014, she appeared in The Assets. In Noble, she played Christina Noble. In 2014, she appeared as Saxon princess Judith in the television series Vikings. Judith should have become one of the main figures during the third season of the series; however, Greene refused because she wanted to appear on Broadway. In 2015, she played Hecate Poole in Penny Dreadful. In 2019, she began to play one of the leads on Dublin Murders, as Detective Cassie Maddox.