Education
O'Sullivan attended the Gaiety School of Acting in Dublin and joined the Abbey Theatre in 1991.
O'Sullivan attended the Gaiety School of Acting in Dublin and joined the Abbey Theatre in 1991.
At the National she has played in Liolà, Mutabilitie, and The Cripple of Inishmaan. She garnered major acclaim for her performance as Widow Quin in Druid Company's 2004 production of The Playboy of the Western World, which toured throughout Ireland including her native Kerry, and also starred Cillian Murphy and Anne-Marie Duff. Keane and was consequently nominated for Best Actress in the Irish Times Irish Awards.