- Dexter Morgan
Dexter is the anti-hero of the series (obviously, since it’s called Dexter). To the public he comes across as a quiet, good-looking blood spatter analyst, who has a quirk for solving mysteries, but on the inside he’s completely different. Due to a horrendous event in his childhood, Dexter is fuelled by his inner “Dark Passenger” to kill. However, due to the Harry code Dexter kills only those who have gotten away with murder (or rape) and slipped through the judicial system-and he makes sure to never to leave a trace.
It is important to note that while the television and book Dexters are mostly similar, the book Dexter is far colder than the teleivison series portrays him. He may come across as nice, jovial and loving but in reality he loves no-one; he literally does not think he can. It isn’t until the fifth book in the series, Dexter is Delicious, that we see him begin to love again with the birth of his daughter, Lily Anne.
- Deborah Morgan
Deborah Morgan is Dexter’s younger foster sister. Although she appears beautiful and sweet she’s got a mouth like a gutter with a matching attitude, and she’ll do whatever she can to get her way. At the beginning of the series she is a police woman working with vice but as the series progresses she joins Homicide and eventually becomes a Sergeant.
In the book series she finds out about Dexter’s secret at the end of Darkly Dreaming Dexter (when his brother tries to kill her) and eventually comes to terms with it; however, in the television series she is blissfully unaware. Also in the book series she has a love affair with older FBI agent Kyle Chutsky, whom she becomes pregnant to. This is similar to the television show as she starts a relatiionship with FBI agent Frank Lundy, though he is shot dead before it becomes more serious
- Rita Morgan
Rita Morgan’s character is almost the same as in the books, except she is a lot stronger than she is originally portrayed. She plays Dexter’s girlfriend (and essentially his cover) and eventual wife, though she has no idea about Dexter’s true personality. She has had a rough life with a husband that used to beat her and her children before he was sent to jail.
In the television series she is killed by the Trinity killer at (quite literally) the very end of the fourth season, though she continues to go strong in the books.
- Astor and Cody
Astor and Cody are Rita’s children from her previous marriage. In the television series they are portrayed as normal children; Astor becoming a teenage girl (and therefore a pain in the butt) and Cody as a happy boy. However, in the book series they are deeply affected by their father’s actions, and like Dexter, they are fuelled by their own Dark Passengers to kill.
- Lt. Maria La Guerta
In the books La Guerta dies at the end of the first novel; which is a good thing because she was a pain in the ass who was beginning to suspect Dexter. However in the show she is a prominent character, who has both good and bad flaws; she’s a good, if overly ambitious, leader who wants what is best for her team and Miami as a whole.
She has a few relationships, although there are two that display her true character. At the beginning of the second season she starts sleeping with a unknown man; who we quickly learn is the partner of the woman who has taken her position. We soon learn, after this woman is fired for being too emotional, that La Guerta was hoping for this all along. At the beginning of the fourth season she starts a relationship with fellow co-worker Angel Batista, and they eventually get married so they can keep their jobs.
- Angel Batista
Angel is a sergeant on the Homicide squad who is close (or as close as one could be) friends with Dexter. He has a friendly, open nature and is kind to almost everyone…while still being tough enough for his job. At the beginning of the television series we learn that he and his wife have separated but he is still having trouble accepting it. Throughout the television show he has a series of relationships, but none become serious until he marries his boss, Maria La Guerta.
- Vince Masuoka
While his character is no that prominent in the books, Vince is a staple addition to the television series. Another “lab rat” like Dexter, he does all the forensic work. However, while he excels at his job his personality is what shines (so to speak). Vince has an incredibly dirty mind. While often fellow Homicide workers display disapproval at his crude jokes, it’s clear that without him there would be a lot more tension throughout the squad.