When Honor Blackman quit the role of Cathy Gale on The Avengers in 1964, just as the show was poised to become an international hit, there was much speculation about who could possibly replace her. One name not in the frame was Blackman’s pal and Diamond City co-star, Diana Dors. When Diana Rigg eventually stepped into the role of Emma Peel, the future of the Patrick Macnee-starring spy-fi show was assured.