Flannigan was born in Inglewood, California. She began acting professionally in 1985. She attended the University of Southern California.
Flannigan has also acted in films. She starred in Teenage Bonnie and Klepto Clyde (1993), National Lampoon's Last Resort (1994), Written in Blood (2003), A Day Without a Mexican (2004), and Homecoming (2005). In 2010 she appeared in the film Do Not Disturb, which she also co-produced.
