Dexter Morgan is introduced as a serial killer who kills other killers who have escaped from, or haven't been found by the justice system. By day he is a blood spatter analyst who works for the Homicide Department of the Miami Metro Police. He is called to murder scenes involving mutilated bodies, but with no blood visible. The murderer, nicknamed the "Ice Truck Killer", intrigues Dexter with this intricate methodology and a personal message in form of a mutilated doll. At the same time, Dexter's sister Debra, a vice squad officer, tries to gain a transfer into the Homicide Department.