One of eight children in an Irish Catholic family, Murphy says that he grew up 'in an arena of constant performance and mimicry' (Murphy's cv, 2005). At the age of sixteen he booked a local hall in Queanbeyan and put on a staged reading of his first play, For God, Queen and Country, which dealt with homosexuality in a small rural town. It was afterwards performed by Canberra Youth Theatre and won awards including the Sydney Theatre Company's Young Playwrights' (ICI) Award.
Tommy Murphy was named Singapore Airlines Young Shakespearian of the Year in 1997. In the same year he was chosen to represent Australia at the 1998 United Nations International Youth Conference in The Hague in July and won the Sydney Theatre Company award for young playwrights.
He attended Sydney University and became President of the Sydney University Dramatic Society, where he directed a variety of works including The Operating Theatre Festival three years running and three 24 hour non-stop plays involving up to 200 actors each time. He graduated from the NIDA Directing course in 2004, and as well as continuing to write plays, he has also directed his own work and that of other dramaturgs. He has adapted works by Marlowe and Shakespeare for the Australian Theatre for Young People, and in 2004-2005 he was one of five Emerging Writers in Residence at the Griffin Theatre Company. Murphy's Strangers In Between was the result of this residency and was included on Griffin's 2005 programme. At this time he also wrote the stage adaptation of Timothy Conigrave's autobiography Holding the Man, for which he later wrote the sceenplay for the film adaptation produced in 2015. Holding the Man has been produced annually around Australia and internationally.
Murphy has had a stellar career with numerous awards, writer-in-residences, and successful productions by leading theatre companies in Australia and internationally. His stage and screen plays have been published by Currency Press.