Dexter Morgan

In 1991, Dexter is fresh out of college and starts as a forensics intern at Miami Metro. The urge to kill is already there, and Harry, his adoptive father, starts guiding every step. His first victim is a nurse who kills patients. From then on, Harry teaches him to pick guilty targets, clean the scene and leave no trace.

Meanwhile, Dexter follows the kidnapping of Captain Aaron Spencer's son. The investigation leads to Spencer himself, and Dexter kills him on a boat.

Years later, Dexter is Miami Metro's blood expert, dates Rita, a mother of two scarred by a violent ex, and kills by the Code of Harry, who is now dead. A killer starts leaving chilled, bloodless bodies and sending messages only Dexter understands.

The case leads him to a buried memory: as a small boy, he saw his mother killed in a shipping container. The killer is Brian Moser, his biological brother, who was there with him that day. Brian wants Dexter to kill Debra so the two of them can be together. Dexter saves his sister and kills his brother.

Police find the bodies Dexter dumped at sea and start hunting the Bay Harbor Butcher. Doakes learns the truth but dies before he can tell anyone. Dexter also learns Harry killed himself. Later he befriends prosecutor Miguel Prado, who turns into a threat, and marries Rita, already pregnant with Harrison.

Now a father, Dexter studies the Trinity Killer, Arthur Mitchell, who seems to have balanced family and murder for 30 years. Dexter kills Arthur but is too late: Arthur has already killed Rita, and Harrison sits in her blood, just as Dexter once did.

Alone with Harrison, Dexter helps Lumen Pierce get revenge on the men who tortured her. Later, Debra sees him kill Travis Marshall and learns everything. To protect her brother, she kills LaGuerta and sinks into guilt.

In the final season, psychiatrist Evelyn Vogel reveals she helped build the Code. Dexter falls for Hannah McKay and plans to run to Argentina with her and Harrison, but Oliver Saxon shoots Debra, leaving her brain dead. Dexter kills Saxon, carries his sister's body out to sea and sails into a hurricane. Everyone thinks he's dead. He becomes a lumberjack in Oregon.

Ten years later, Dexter lives in Iron Lake, upstate New York, as Jim Lindsay, and hasn't killed in years. Harrison's arrival and the discovery of killer Kurt Caldwell wake up his old side. Dexter kills Kurt, but police chief Angela Bishop arrests him as the Bay Harbor Butcher. Escaping, he kills an innocent cop, and Harrison sees who his father really is. Dexter asks his son to shoot.

Dexter survives. Ten weeks later, he heads to New York after Harrison and gets into billionaire Leon Prater's club of killers by posing as one of them. Angel Batista, his old Miami colleague, gets close to the truth but is killed by Prater. With his son's help, Dexter kills Prater and takes his yacht and the club's files.

Dexter comes from Jeff Lindsay's novels, starting with Darkly Dreaming Dexter (2004). Only S1 adapts a book; the rest goes its own way. Michael C. Hall, previously David Fisher on Six Feet Under, won the Golden Globe for best actor for the role in 2010.