Mac show's the gruesome photos to the parents of the missing girl.
A body of a man is found on the Bridge. Evidence that is found at the scene leads Mac to believe there might be two homicides, not one.
A suspect cuts through the woods trying to get away.
During an argument over The Mets vs.Yankees, the suspect rides by on a bicycle.
Mac and Jo find Mary.
Mac and Jo find out a restaurant in the Haight Ashbury neighborhood of San Fransico is a front for drug running.
Jo catches her daughter with her boyfriend in an uncompromising position.
Brook's victim is found to have been broiled and not burned by the fire created in the elevator. Meanwhile, Mac and Jo try and figure out why Brooks has advanced to hurting people and not just property.
Mac is stunned at Brook's latest victim, whose fate was to be burned internally.
Flack is impressed by the newest detective, Jamie Lovato.
Leonard prepares to murder the girl who stood by and watched him get abused as a child but Mac has other plans.
Rob Morrow returns as Arsonist Leonard Brooks and claims another victim.
Leonard Brooks returns after fifteen years and Mac rushes to figure out why.
While an angry mob is outside, Mac and Detective Flack question a New York police officer about a fatal shooting.
Jo goes down to the lab to discuss new evidence with Sheldon.
Adam makes it back to the precinct safely but figures out the victim had nothing to do with the robbery.
Adam and Sheldon take Mac and the NYPD officer on a virtual tour of the scene of the shooting.
Mac asks the victim's girlfriend to come down so she can hear the truth firsthand.
Mac questions an ex-cop about a Valentine's Day shooting.
It's Valentines Day and there are three murders of love.
Guest star Josh Groban provides some very romantic music for Mac and his love.
Lovato and Flack discuss their Valentine's Day plans. Sid gives Lindsay some interesting news about one of the victims.
Messer interrogates a suspect about the murder of her husband. Love really is blind.
Mac and D.B. Russell watch the meeting from a surveillance van. A shootout in the middle of the street causes chaos.
During the autopsy, Christine's fingerprint is found in a blood drawing on the body.