Mary Louise Weller, born September 1, 1946, is an American actress and model. She began her career as a successful model, gaining international visibility with her appearance on the cover of the 1970 *Sports Illustrated* Swimsuit Issue. Her transition to acting culminated in the role for which she is best remembered, as student Mandy Pepperidge in John Landis's cult comedy *Animal House* (1978). Her filmography, concentrated mainly in the late 1970s and early 1980s, includes appearances in films such as the horror *The Evil* (1978), the film adaptation of *The Bell Jar* (1979), and *Blood Tide* (1982). She also guest-starred on popular television series of the era, including *Kojak*, *Starsky & Hutch*, and *Fantasy Island*. After retiring from acting, she successfully pursued equestrianism, competing at the national level.