Colette O'Neil was born in Glasgow in 1937 and played the role of Ruth Winter in Coronation Street between May and July 1966. Her career includes roles in Doctor Who, Monarch of the Glen, and numerous roles in Dr. Finlay's Casebook.

Colette has also appeared in Brian Clemens' Thriller, The Power Game, Adam Adamant Lives! and the film The Smashing Bird I Used To Know with Patrick Mower and Dennis Waterman.

After school she went to Glasgow University, intending to take a Bachelor of Science degree in pharmacy however after taking drama lessons in her spare time, she successfully auditioned for a repertory company. She went on to work for Royal Court Theatre and the Royal Shakespeare Company. She was spotted by Coronation Street producer Peter Eckersley in an ITV production of D.H. Lawrence's The Blind Man opposite Patrick Allen thought her right for the part of Ruth.