Having started out as a child model, Katherine appeared in her first feature film, That Night (1992), at the age of 13. She's since been seen in King of the Hill (1993), My Father the Hero (1994), Under Siege 2: Dark Territory (1995), Bride of Chucky (1998), and The Ringer (2005). Heigl, however, is best-known for her work on television, where she played Isabel Evans on the WB's Roswell from 1999 to 2002, and Dr. Isobel Stevens on ABC's Grey's Anatomy since 2005.