She is best-remembered on television for her co-starring role in the early 1980s ITV children's fantasy series Into the Labyrinth as the evil witch Belor, and her late 1980s guest role in the BBC soap opera EastEnders as shady mafia affiliate, Joanne Francis. She has also been seen in two adventures of Doctor Who: as Toos in The Robots of Death(1977) and as Professor Rachel Jensen in Remembrance of the Daleks (1988), a role she reprised for Big Finish Productions' officially licensed audio drama spin-off series Counter Measures. She was also heard as one of the many voices of Xoanon in The Face of Evil (1977). She had auditioned for the role of the Fourth Doctor's companion Leela but the role went to Louise Jameson. Salem also had a recurring role in the British sitcom French Fields from 1989 to 1991.
Other television guest appearances have included roles in popular British series such as Out of the Unknown, Blake's 7, The Onedin Line, The Professionals, Howards' Way, Ever Decreasing Circles, Tripods and All Creatures Great and Small, and later on in American series including Magnum, P.I., Party of Five, ER and The West Wing where she played a British prime minister.
She died on the 21st February 2024 at the age of eighty.