Tommy Sexton was born, the middle child of nine, in St John's, Newfoundland. He displayed talent as a young child, winning awards as a boy soprano in the Kiwanis Musical Festival, making his theatrical debut playing the lead in an all-boy school production of Alice in Wonderland, and playing the title role in a production of Oliver!

At 14, he joined the Newfoundland Travelling Theatre Company, where he met many of his future Codco alumni, touring with productions See How They Run, Pool's Paradise and Starrigan.

At 16, Sexton went to Toronto and was hired by Global Theatre. He made his TV debut in the series "Police Surgeon". Tommy and some other young Newfoundland actors raised $300 from Theatre Passe Muraille to write and produce Cod on a Stick. Thus Codco was born, going on to create a string of successful satiric revues and a hit TV show that ran for seven seasons.

The Plays of CODCO was published in 1992. Working with Greg Malone, he performed in the revue Two Foolish to Talk About; the TV mini-series The S and M Comic Book; and the TV special The National Doubt. He also performed with the Wonderful Grand Band, both in live venues and on TV. Sexton won numerous awards, including Geminis for comedy performance and writing. He died in St. John's, Newfoundland, at the age of 36 of AIDS-related complications.

His sister, filmmaker Mary Sexton, produced a warm and funny tribute to Tommy in 2001, with her debut film Tommy... A Family Portrait.