Adrienne Hill
From Tardis Wiki, the free Doctor Who reference
Adrienne Hill (born Plymouth, England; died 6 October 1997) played companion Katarina from Episode 4 of "The Myth Makers" to Episode 4 of "The Daleks' Master Plan." Katarina was the first and one of the few companions to be killed in the series, and her tenure in the show was among the most brief.
Adrienne Hill also appeared in the 1985 "Children in Need" special, together with other Doctor Who cast members. She died from cancer in 1997, with her last known acting role, that of a library assistant in an episode of City Life, being broadcast potshumously in February of 1998.