Helen Christine Blatch (née Wilson; 24 January 1934 – 31 December 2015) was a British actress on stage and screen, best remembered on screen for her roles in Doctor Who (in the serials The Deadly Assassin and The Twin Dilemma) and The Practice, and on stage for her casting as "Cerimon, a lord of Ephesus", in the Royal Shakespeare Company's 1989–1990 performance of Pericles.