The team finds three young women, all of whom appear to have been brutalized in the same way. The only witness they have is the surviving young woman, who can communicate only through blinking. Photographs found at one of the crime scenes lead the team to a couple that had sponsored one of the victims, and the boyfriend who claims he hasn't spoken to her in weeks.

After mounted officer Valasquez is shot down in the park, Mac goes looking for the bullet that killed the officer only to learn that it is lodged in the horse's spine and cannot be removed without being fatal to the horse. The investigation leads them to a local street vendor, but stalls when the D.A. asks Mac not to do anything to risk the horse until after the woman who donated it has a chance to say goodbye. Aiden investigates the body of a young man, Lenny Starks, who was found face-down, dead in the street. Aiden traces the young man to a local pizza parlor where she faces intimidation from the bookies who use it as a gambling front.

Mac and Stella investigate the murder of a woman who was stabbed in the heart with a wooden stake. The police arrest a woman who was kneeling over the body with blood on her, but Mac isn't convinced that she committed the crime.

The team's investigation into the death of Hannah Bloom, who died at her own wedding, is put on hold when her father refuses to allow them to perform an autopsy until after his daughter's body is blessed by a rabbi. Danny and Mac turn their attention to the woman who trained the doves who were supposed to be released, but cannot tie her directly to Bloom, who died from formaldehyde poisoning. Stella, Flack and Aiden investigate when a hand is found deep underground, and soon realise that the dead man, Rick Amadori, chewed off his own hand. It seems like a slam dunk when the son of a man Amadori killed three years earlier confesses to the crime, but things aren't as easy as they seem.

A woman's death leads our detectives to a school for sexual fetishes such as bondage and spanking.