After leaving school, Sears spent time in Paris performing voiceover and dubbing work and socialising with artists and writers such as Pablo Picasso, Albert Camus and Arthur Koestler.

At 21, Sears replaced Mary Ure in the part of Alison in John Osborne's Look Back in Anger, playing alongside Alan Bates and Richard Pasco.

On screen, she was cast in Room at the Top (1959) as Susan Brown, the naive daughter of an industrial magnate (Donald Wolfit) who falls for social climber Joe Lampton (Laurence Harvey).

Sears travelled to Australia to appear in the last Ealing Studios film, The Siege of Pinchgut (1959), in which she played a hostage who forms a romantic liaison with an escaped convict.

[5] One year later, in the film adaptation of Lawrence's semi-autobiographical novel Sons and Lovers (1960) directed by Jack Cardiff, she appeared as Miriam, the girlfriend and intellectual companion of Paul Morel (Dean Stockwell).

She also appeared as Grusha in Brecht's The Caucasian Chalk Circle at the Chichester Festival Theatre in 1969 and in Alan Ayckbourn's comedy How the Other Half Loves in London's West End.

Sears died at the age of 58 in early 1994 of multiple organ failure caused by cancer at the family home in Hinchley Wood near Esher, Surrey.