Allen appeared on television programs such as Captains and the Kings, The Incredible Hulk, Ironside, The Rockford Files, Alias Smith and Jones, Bonanza, Kojak, Gunsmoke, Love, American Style, Columbo: Lovely but Lethal, Cagney & Lacey, Adam-12, and Hawaii Five-O. In 1974 she was the lead Actress in the western Billy Two Hats, alongside Gregory Peck and Jack Warden. In 1976, she portrayed Anne Morrow Lindbergh in the television movie The Lindbergh Kidnapping Case, based on the real-life Lindbergh baby kidnapping/murder. Her last role was in an episode of L.A. Law in 1990, after which she retired from acting.