Dexter is an American television crime drama mystery series that aired on Showtime from October 1, 2006, to September 22, 2013. Set in Miami, the series centers on Dexter Morgan (Michael C. Hall), a forensic technician specializing in blood spatter pattern analysis for the fictional Miami Metro Police Department, who leads a secret parallel life as a vigilante serial killer, hunting down murderers who have slipped through the cracks of the justice system. The show's first season was derived from the novel Darkly Dreaming Dexter (2004), the first in a series of novels by Jeff Lindsay. It was adapted for television by screenwriter James Manos Jr., who wrote the first episode. Subsequent seasons evolved independently of Lindsay's works.

In February 2008, reruns (edited down to a TV-14 rating) began to air on CBS in the wake of the shortage of original programming ensuing from the 2007–08 Writers Guild of America strike, thus the reruns on CBS ended after one run of the first season. The series enjoyed mostly positive reviews throughout its run and popularity. The first four seasons have received universal acclaim, although reception dropped drastically as the series progressed. The show has also won many awards, including two Golden Globe awards won by Michael C. Hall and John Lithgow for their roles as Dexter Morgan and Arthur Mitchell, respectively.

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