At school, Van Ost became the youngest adult dancer at the
London Palladium before moving into films and television at age 18. She appeared in four
Carry On films -
Carry On Cabby (1963), ''
Carry On Don't Lose Your Head (1967), Carry On Doctor (also 1967) and Carry On Again Doctor (1969). Her other film roles included The Beauty Jungle (1964), Mister Ten Per Cent (1967), Casino Royale (1967), Corruption (1968), The Smashing Bird I Used to Know (1969), Incense for the Damned (1971), and the Hammer horror film The Satanic Rites of Dracula (1973). She appeared as the dim-witted Penny in an episode of The Avengers'' entitled "Dead Man's Treasure" (1967), and a year later was considered for the part of
Diana Rigg's replacement as
Steed's sidekick. She also appeared in the 1966 mini-episode of the same series entitled "The Case of the Missing Corpse" (broadcast in the U.S. but not in the U.K.) made to advertise the change to colour of the previously black and white production. In addition she appeared in the ITV series, Mrs Thursday (1966), in the second episode of the first series as Sandra Willing, a potential secretary. ==Post-acting==