The first season of Dexter is an adaptation of Jeff Lindsay's first novel in the Dexter series, Darkly Dreaming Dexter. Subsequent seasons have featured original storylines. This season aired from October 1, 2006 to December 17, 2006, and follows Dexter's investigation of "The Ice Truck Killer". Introduced in the first episode, "Dexter", this serial killer targets prostitutes and leaves their bodies severed and bloodless. At the same time, Dexter's foster sister, Debra Morgan, a vice squad officer, aspires to work in the homicide department, and Dexter's girlfriend, Rita Bennett, wants their relationship to be more intimate. Christian Camargo appears as Rudy Cooper and is a recurring character until the end of the season.
The show's first season received generally favorable reviews from critics; it was praised as "bold, different and exciting, with a central character and performance that take your breath away" by the New York Daily News. The Wall Street Journal saw "the grotesqueries of Dexter" as "not something that can easily be dismissed with the old "you don't have to watch" line", and concluded that "We do have to live among the viewers who will be desensitized, or aroused, by this show". The aggregate site Metacritic scored the show's first season at 77 out of 100 based on 27 critics reviews.
Dexter is a forensic expert in blood patterns who works with the Miami Police Department. He is also a serial killer, who kills people that the police can't bring to justice. He has to hide his double life from his sister, his girlfriend and his co-workers. He is intrigued by a killer who has found a way to kill girls without leaving blood behind.
Being wrapped up in preparing for his next victim, Dexter, finds out that the Ice Truck Killer is aware of Dexter's dirty little secret.
Dexter's on the trail of a recently released murderer who plans to kill again when he's sidetracked by the Ice Truck Killer's latest crime - a cut-up hooker found in a hockey ice rink.
The Ice Truck Killer begins leaving pictures from Dexter's childhood at the crime scenes. Is the killer trying to tell Dexter something about his own past?
While the rest of the police department are focused on finding the Ice Truck Killer, Dexter is busy gathering evidence for his next victim. It turns out he will also discover more about relationships, love and how to make a success of it all. In doing so he gets some hilarious advice from unlikely sources and we see the first time that he actually kills two people at one time.
Dexter is called to the scene of the crime at the Castillo junkyard. The Ice Truck Killer has returned Valerie Castillo's body putting Dexter in danger of being caught. A boy is found who witnessed the crime.
The police identify the Ice Truck Killer. However Dexter feels there is something wrong with the suspect. Dexter must also deal with Paul, Rita's recently paroled husband.
Dexter suspects rich women's shrink of murder. When he visits the shrink, he is surprised by a dark secret from his past.
Dexter receives notification that his biological father has recently passed away. Dexter is named as the sole heir of all his possessions including his house. Dexter goes for a weekend away with Rita, Deb, and Rudy.
The Ice Truck Killer is back. He leaves a crime scene that brings back some horrifying repressed memories for Dexter. Paul sues Rita for sole custody of Astor and Cody.
The Ice Truck Killer puts Dexter in a life changing position when he takes someone close to Dexter hostage. Doakes begins to suspect that Dexter's odd behavior is something darker than he originally thought.