Katherine Heigl is an American actress. She played Izzie Stevens on the ABC television medical drama Grey's Anatomy from 2005 to 2010, a role that brought her recognition and accolades, including the Primetime Emmy Award for Outstanding Supporting Actress in a Drama Series in 2007.

Isobel Katherine Stevens, M.D. is a fictional character from the medical drama television series Grey's Anatomy, which airs on the American Broadcasting Company (ABC) in the United States. The character was created by series producer Shonda Rhimes, and was portrayed by actress Katherine Heigl from 2005 to 2010. Introduced as a surgical intern at the fictional Seattle Grace Hospital, Izzie worked her way up to resident level, while her relationships with her colleagues Meredith Grey, Cristina Yang, Alex Karev and George O'Malley formed a focal point of the series.