Two of her most notable roles are Barbara in Omen III: The Final Conflict (1981), and Leueen (a character who took on the actress' name during production), Lois Lane's fellow Daily Planet reporter in Superman II (1980). Her character, incidentally, is not present in Richard Donner's version of the Superman movie. Willoughby also appeared in a small role in the first Superman movie, playing an unnamed secretary, and was one of the voice actors who worked on the original BBC radio production of The Hitchhiker's Guide to the Galaxy, amongst other roles in British and Canadian theater, film and television