In the 1984 film The Terminator, she had a pivotal role as a woman named Sarah Connor, who is murdered by the Terminator because she shares the name of its target. Also in 1984, she appeared in the hit comedy film Revenge of the Nerds as the woman who answers the door where Harold Wormser goes to ask about the room for rent. In 1994, she played the role of Diana Beaujolais in Saved By the Bell: Wedding in Las Vegas.

She married Air Force officer Joseph T. “Tom” Norris Jr. on May 7, 1988.

She played the role of Sophie, a waitress, in the movie Return to Me which was directed by and also starred Bonnie Hunt and then later appeared as a series regular on Bonnie’s comedy series, Life with Bonnie as “Gloria”, the housekeeper, for two seasons until the show ended. She also appeared in The WB television series Charmed episode “Primrose Empath”. She also has a recurring role on the soap opera Passions, playing the disturbed character of Norma Bates. She also played the nanny on Melrose Place and a no-nonsense mother hosting a Halloween party on Highway to Heaven. She guest-starred in one episode of Will and Grace, in one episode of Anger Management and in one episode of How I Met Your Mother. In 1991, Muellerleile appeared on the situation comedy Night Court as Miss Gilly, as well as playing three different characters in three other episodes of Night Court..