The series is basically about a blood-splatter analyst for the Miami PD called Dexter, who also happens to be a serial killer. He follows what is known as the 'Code of Harry' in order to satisfy what he calls his Dark Passenger. The Code was taught to him by his step-father, a cop, so that he doesn't get caught and in order to use the darkness for good. He only kills people that have slipped past the law- murderers, paedophiles etc.
Like many other serial killers, Dexter has a very precise ritual that he carries out for each of his kills. He must first be absolutely certain that his victim is guilty. He can research into their lives for months, finding evidence that pins them to their crimes. He then finds a kill room; somewhere out of the way like a garage or a shed. He fills the room with plastic shrink wrap, covering every single piece of furniture so that he leaves no trace. He finishes the room off with pictures of the person's victims propped up in photo frames around the room. He takes the criminals by drugging them, using a needle, tying them down to a table using duct tape and cuts their clothes from them so he doesn't get blood on them. When they regain consciousness, they find themselves taped to a table and unable to escape. Dexter then explains what they've done to get themselves in that position, takes a sample of blood from their cheek and kills them using one of his many tools. He chops them up post-mortem and disposes of them in the lake.
The first book focuses on one notorious killer dubbed by the press as 'The Icetruck Killer', who for some reason wants to get to know Dexter a little better. The Icetruck Killer kills hookers that he drains the blood from, chops up into little pieces and then wraps up "like little packages".
