She was born Clare Tracy Compton Pelissier, the daughter of the director Anthony Pelissier and the actress Penelope Dudley-Ward. During a film-acting career that lasted from the early 1960s until 1975, she appeared in about thirty movies. She is probably best known for her role as the mistress of General Buck Turgidson (George C. Scott) in Dr. Strangelove (1964). She has the only female part in that film but is seen in only one scene--when she answers the phone while Turgidson is in the bathroom (however, she is shown in the copy of Playboy magazine being read by Slim Pickens in the B-52 with a copy of Foreign Affairs strategically draped across her behind). She was also considered as a replacement for Diana Rigg in The Avengers.
Tracy Pelissier took the surname of her stepfather, Sir Carol Reed, following her mother's remarriage in 1948.