The FBI are called to the investigation of the murder. The blond we first saw, is a prostitute and the agents are trying to get a serial killer whose M.O. is the same. This criminal will murder men that have engaged in sex with prostitutes, then proceeds to steal their cars. Colby and Nikki are warned about having spotted the victim's car, now going to a desolate area, they give chase, but their official vehicle suffers an accident, where she is badly hurt.
Charlie Eppes is consulted to help the investigation. He compares the murders to the movement of sharks in the ocean. The agents are interested in Jack Steves, a man that has a group that advises ladies that engage in prostitution. The federal think he might know who is the guy that is using the women in order to kill and rob the men. Professor Russell Lazlo, a motorcyclist enthusiast, who has been trying to interest Don into joining a group, is the one that discovers that one prostitute that died in circumstances similar to the new cases, was a hemophiliac. The agents discover she had a sister who might help them get to the criminal they want.
An interesting episode directed by Stephen Gylenhaal, who is a frequent contributor to the series. The chapter was written by Julie Hebert. The regular cast and guest stars came together in this installment to make the viewer keep his attention to the criminal case being told. Tony Hale as Laz, has some funny moments. Anna Camp, Clea Duvall and Kritin Richardson are featured.