A dark and compelling Dexter theory reinterprets the titular serial killer as a victim, and it entirely reframes the entire show's story. Dexter follows Dexter Morgan as he attempts to balance his career as a bloodstain pattern analyst for the Miami Metro Police Department with his family life and his hobby of murdering other serial killers and murderers. Running for an initial eight-season run, Dexter then returned for 10-episode limited series, Dexter: New Blood.
The show painstakingly covers Dexter's dark origin as a killer: after witnessing the brutal murder of his mother, Dexter was adopted by police officer Harry Morgan. Harry noticed psychopathic tendencies and a fascination with death in Dexter and taught him to channel it into vigilantism — namely, into killing heinous criminals who slip through the cracks of the justice system. Harry's guidance leads Dexter to become the Bay Harbor Butcher, and it's what allows him to lead his murderous double life.
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However, a fan theory posted to Reddit posits that Dexter was never a psychopath at all, and it changes everything. The theory claims that Harry incorrectly identified Dexter as a psychopath, when in fact, he was just an autistic child struggling to come to terms with his witnessing of his mother's brutal murder. Harry's code made Dexter a killer, but the compelling theory suggests that the character's murderous streak was in fact a manipulation perpetrated by Harry (and later by Dr. Vogel). Dexter's desire to kill would in this interpretation come from his mentor's teachings turning him into a murderer as a result of the lifestyle he had adjusted to throughout his youth, instead of any
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