The first ABC promo for episode four of the new, fourth Grey's Anatomy season, "The Heart of the Matter." Looks like Izzie and Callie are going to throw down - and plenty of other interesting things are transpiring.

A slightly different preview of "The Heart of the Matter," courtesy of CTV. Looks like another good episode in the works... except maybe for the loser of the Izzie-Callie fight.

A sneak preview of "The Heart of the Matter," the fourth episode of Season Four of Grey's Anatomy. Lexie and Cristina treat a young patient with severe head trauma whose father is verbally abusive. Cristina is also a bit abusive in her own right, as Derek points out. Very intense.

This is another sneak peak at "The Heart of the Matter," the fourth episode of Season Four of Grey's Anatomy. Callie and Izzie are preparing to throw down... and the meek George is caught in the middle of a fight he doesn't want a part of. Put your dukes up!

A preview of "Haunt You Every Day," the fifth episode of season four of Grey's Anatomy. From ABC.

A sneak preview of Izzie and Cristina from "Haunt You Every Day." Dr. Hahn and a decision she made are the topics of this conversation they have, as is Izzie's sleeping with George.

Another sneak peak at "Haunt You Every Day." In this minute-long clip, Meredith talks to Derek about her mother's ashes... which she for some reason has with her. Pretty funny.

Meredith and Richard dispose of Ellis' ashes in a way Mer feels her late mother would find most appropriate. Once again, the Chief (James Pickens, Jr.) captures the scene with quiet grace and dignity.

The nurses have compared notes, and techniques, and pickup lines, and formed a group that is wholly united against Mark Sloan. Funny stuff involving the resident plastic surgeon and man whore.

Cristina and Callie amputate a patient's foot and discuss some of the recent trials and tribulations in their romantic lives. It's a great scene from "Haunt You Every Day."

The first preview of "Kung Fu Fighting" from Season Four. It looks like a good episode with a lot going on!

Michael Phelps is coming to Grey's Anatomy. Not really. But this skit from Jimmy Kimmel would imply as much.