As Cristina tries to recover, she proves to be a very difficult patient, and a visit from her mother doesn't improve her demeanor any. And Meredith's mother, Dr. Ellis Grey, has the hospital staff running in circles.

The staff tries to prevent a patient from getting an elective surgery. Cristina tries to help Preston cope with the after effects of his surgery. A patient bails on their surgery. Someone goes to a bed-and breakfast. Alex deals with a patient who has had a high amount of injuries in the past. A man undergoes surgery. Before the surgery his wife was only somewhat supportive, but the results may be too much for her to handle. Izzie tries to go back to the hospital for the first time since Denny died. One child's constant visits are noted by a nurse. Two foster patients are met with suspicions of child abuse. George and Callie's relationship moves forward.

The doctors meet the world's oldest intern. Marcy brings in her son Henry because she finds his change in behavior suspicious. A patient named Connie may lose her vocal chords unless Mark and Richard can perform a radical new surgery. George impresses the other interns at work but at home he is trying to deal with his guilt about having sex with Izzie.

It's Halloween at Seattle Grace! There may be jokes, pranks, and/or scare tactics. Some of the women form a club based on an experience they all share. A man volunteers for what most of the doctors believe is an unnecessary surgery. One of the patients is in the hospital because they tried to carve a pumpkin in an unconventional manner.

Izzie and George's new-founded relationship results in them having bad sex. Callie's Chief Resident position is taken away from her, and Bailey is the humble replacement. Meredith can barely handle it with Lexie anymore.

The residents are on their own with the dreaded night shifts while the attendings go out to play to celebrate Derek's grant for his clinical trial.