Gunn was born in Fort Worth, Texas. She graduated in 1980 from W.E. Boswell High School in Saginaw, Texas where she was active in school dramas and plays. She was also a varsity Cheerleader and was elected Homecoming Queen her senior year. Standing at 5'3", she worked at a variety of jobs, including a car saleswoman, personal assistant, FLIGHT attendant with Southwest Airlines and as one of the Dallas Cowboy Cheerleaders for two seasons in the early 1980s. Her opening into acting began as Susan Howard's stunt double on the television series Dallas in 1988.
Gunn had starring role of Kelly Cochran in the CBS series Dark Justice from 1992 to 1993. From 1996 to 1999, she starred as Detective Cassandra St. John on the USA Network series Silk Stalkings. Gunn also guest starred on In the Heat of the Night, Dream On, Diagnosis: Murder, CSI: Crime Scene Investigation and Crossing Jordan. Her film credits include Night of the Running Man (1995), The Quest (1996), The Nurse (1997), and Getting There (2002).
