Trent Gill

Derek and Meredith get ready for their wedding; college students injured in a car accident are admitted to the ER; Izzie starts experiencing familiar symptoms.

When a nurse confesses to six mercy killings, the team reopens a 1998 case involving a terminally ill man who died suspiciously.

In the hospital morgue, Melinda investigates a haunting -- involving the death of a surgeon.

When a college student is beaten, shot to death and his apartment ransacked in what appears to be a drug-related hit, the team must track down his killers. After examining the evidence in the murdered student's apartment, the team finds traces of pure, unprocessed heroin and discovers that the victim had a female roomate who is now missing. Meanwhile, Stella's aggressive interrogation tactics with a witness threaten her police badge.

The brother of a mentally impaired man is found dead; a con man rents the same apartment to multiple parties; Sipowicz and Clark clash with Bale when charges are filed against a nervous father who offers them a bribe.