Director Peter Weir saw her in a television commercial for Fanta playing the fancy Nancy character and felt she was perfect for the lead role in Picnic at Hanging Rock.

[1] During 1975, she appeared in a recurring sketch in comedy series The Norman Gunston Show called "The Checkout Chicks".

This sketch, a send-up of melodramatic soap operas set in a supermarket, mostly featured other former Number 96 actors – Vivienne Garrett, Candy Raymond, Philippa Baker, Judy Lynne, and Abigail.

She has worked steadily in film and on stage ever since, including starring roles in the BBC TV series The Borgias (1981), Cousin Phillis (1982) Peter Greenaway's The Draughtsman's Contract (1982), Breathing Under Water (1991), Seeing Red (1992), The Dirtwater Dynasty and Great Expectations – The Untold Story , A Los Cuatro Vientos (1987),filmed in Spain; and Australian TV miniseries such as Mussolini and I (1985), Fields of Fire 2 (1988), and Tanamera-The Lion of Singapore (1989).

Lambert resides in the Sydney suburb of Balmain with her son (born 1989)[2] and works as a psychotherapist, counsellor, and coach.