Both of Mitchell's parents were heavily involved in theatre and she has had an extensive career in her own right in theatre as well as many television and film roles. She started her own theatre company, Strut Theatre, with other actors to promote women's roles. Strut worked out of Wharf 2 at the Sydney Theatre Company in the early nineties. She produced two plays, "Pam Gems" and "Dusa, Fish, Stas and Vi", as well as a commissioned play by Australian playwright, Justin Fleming called "Conversation Peace". She then moved to Melbourne to appear in the National Tour of the musical "Hello Dolly", produced by John Frost.