"Kung Fu Fighting" is the sixth episode of the fourth season of Grey's Anatomy and the 67th produced episode of the series. It is also the 73rd produced episode of the Grey's Anatomy franchise. It was broadcast on November 1, 2007.
Erica's first day at Seattle Grace pits Izzie and Cristina in direct competition for her attention and a place on the cardio service while George and Izzie finally find themselves free to be together but struggle to find time for eachother. Meredith must council a patient who miraculously survives a deadly free-fall and Mark helps Callie get back at George by involving him with two feuding patients. With his marriage is disaray, Richard turns to the men of Seattle Grace for help.
- "There's thing things about being a surgeron, maybe it's pride or maybe it's just about being tough, but a true surgeron never admits they need help unless absolutly nessesary. Surgerons don't need to ask for help because they're tougher than that. Surgerons are cowboys, rough around the edges, hardcore. Atleast that's what they want you to think."
- "Deep down everyone wants to believe they can be hardcore but being hardcore isn't just about being tough, its's about acceptance. Sometimes you have to give yourself permission to not be hardcore for once. You don't have to be tough every minute of every day. It's okay to let down your guard, in fact there are moment when it's the best thing you can possibly do as long as you choose your moments wisely."
- "Raindrops From The Sun" - Imani Coppola
- "Don't Try To Fool Me" - Miss Li
- "Say A Lot" - Buddy
- "Cheer Me Up Thank You " - New Buffalo
- "Let Somebody In" - The Magic Numbers
- "Merry Happy" - Kate Nash
This episodes' title references the song Kung Fu Fighting, originally sung by Carl Douglas