Warning! This article contains SPOILERS for Dexter: Original Sin season 1, episode 7.The main villain ofDexter: Original Sinwho killed Jimmy Powell and kidnapped Nicky Spencer has been revealed, and the shocking twist needs a bit of explanation. Despite being a prequel,Dexter: Original Sinhas found countless ways to surprise and shock its audience. FromOriginal Sinretconning Dexter’s third killto possibly having acameo appearance from Brian Moser, the prequel show has had many surprises in store. One of its biggest twists came inOriginal Sinepisode 7, and it was so shocking that it may need to be explained.
The question ofwho killed Jimmy Powelland kidnapped Aaron Spencer’s (Patrick Dempsey) son, Nicky, has been one of the biggest mysteries of theDexterprequel show, butDexter: Original Sinepisode 7just solved it.Original Sinepisode 7 saw quite a few developments in the kidnapping case, from Nicky losing a finger but stabbing his attacker to Dexter finding a drop of the kidnapper’s blood on the box. Dexter was even able to figure out who the killer was, butOriginal Sin’s twist villain and his motives need a bit of explanation.

Captain Aaron Spencer Is Jimmy Powell’s Killer & Nicky’s Kidnapper
Dexter Connected Spencer To The Kidnappings After He Saw The Wound Nicky Gave His Kidnapper
As Dexter pieced together,Captain Aaron Spencer is the person who killed Jimmy Powell and kidnapped Nicky Spencer. Earlier in the episode, Nicky fashioned a shank out of the handle of the bucket in his cell, and he used it to stab his kidnapper in the wrist. After Dexter found the killer’s blood on the box that contained Nicky’s finger and saw the bandage on Aaron’s arm, he connected the dots. Then,Original Sintook it a step further to show Aaron buying the same prepackaged meals that the kidnapper fed to both Jimmy and Nicky.
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For now, the only person who even suspects Captain Spencer is Dexter. As Aaron pointed out, the blood types of both his and Nicky’s blood matched, which may be enough to get Tanya Martin and Vince Masuka to look for other evidence. Aaron has also been doing a great job of acting devastated throughout the entire investigation, which makes him an even less likely suspect. On top of it all,Dexter’s only evidence so far is completely circumstantial, so Miami Metro may not be able to prove Aaron is the killer at all.

Why Spencer Killed Jimmy Powell & Is Blaming The Cartels
Aaron Spencer Likely Killed Jimmy & Blamed The Cartels To Throw Miami Metro Off His Scent
ThoughOriginal Sinrevealed Aaron Spencer is the killer, it didn’t reveal his motives.Aaron may have kidnapped and killed Jimmy Powell specifically to make it less likely that the police would suspect him in Nicky’s kidnapping. In many cases where a child with divorced parents is kidnapped, the police immediately look to one of the parents as a suspect. As soon as Nicky was kidnapped, however, the detectives of Miami Metro instantly assumed it was the same cartel that killed Jimmy. Aaron’s history of being tough on the cartels also makes it even more believable that they would target his son.
Every Death In Dexter: Original Sin Season 1
There have been many deaths in the first half of the Dexter prequel series Dexter: Original Sin, including victims, killers, and a few key characters.
Aaron may have also had a secondary reason to blame the cartels for Jimmy’s death and Nicky’s kidnapping. Both of the kidnappings kicked the proverbial hornet’s nest at Miami Metro. Bobby Watt (Reno Wilson) and Angel Batista (James Martinez) mentioned that they’re going after the Los Tigres cartel with everything they have, trying to find their safe house.Aaron Spencer may have blamed the cartels specifically to get Miami Metro to crack down on them. There’s almost certainly no love lost between the police captain and the cartels, and Aaron may have been out solely to put the cartels away for good.

Why Spencer Kidnapped His Own Son & Severed His Finger
Aaron Spencer May Have Kidnapped Nicky To Punish His Wife’s New Fiance & Get Custody Of His Son
As for why Aaron would kidnap his own child and sever his finger, the answer is harder to determine.Aaron was clearly enraged about Becca’s (Amanda Brooks) affair and her new fiancé, Nelson (Travis Myers), inOriginal Sinepisode 4, and kidnapping Nicky may be a way to hurt Nelson. If Nicky is released alive with a missing finger, Aaron could use it as evidence that Nelson and Becca shouldn’t have custody of him, and that he should raise Nicky himself. He could even attempt to frame Nelson for the kidnapping, and get the “homewrecker” out of the picture for good.
If Nicky is released alive with a missing finger, Aaron could use it as evidence that Nelson and Becca shouldn’t have custody of him, and that he should raise Nicky himself.
Targeting his own son specifically may have also been a way for Aaron to get Miami Metro even more motivated to find the cartel they think is responsible.While the death of a judge’s son was enough for Miami Metro to prioritize that case, the threat of their captain’s son dying if they don’t work fast enough would certainly light a fire under the detectives. It could even be enough for Miami Metro to beging killing cartel members as retribution. At this point, however, it’s too soon to tell for certain why Aaron Spencer would kidnap and maim his own son.
What Dexter’s Realization About Aaron Spencer Means For The Rest Of Season 1
Now that Dexter knows that Aaron Spencer killed Jimmy Powell and mutilated Nicky, he’ll almost certainly be a main focus for the rest ofOriginal Sinseason 1.Dexter has already expressed his desire to personally kill Aaron, but he’s going to need Harry Morgan’s (Christian Slater) approval first. Unfortunately, Dexter only has circumstantial evidence to go on, and Harry and Aaron have been friends for years. It’ll be hard for Dexter to convince him that Aaron needs to die, and it could cause quite a bit of strife between Harry and Dexter. It may even factor into Harry’s eventual suicide.
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“And in the Beginning…”
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“Kid in a Candy Store”
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“F is for F***-Up”
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“The Joy of Killing”
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“Business and Pleasure”
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Additionally, Dexter always kills the main villain of each season in the finale, which means he almost certainly won’t get Aaron on his kill table untilOriginal Sinepisode 10.The next episodes ofOriginal Sinwill likely see Dexter search for more evidence to prove that Aaron is the killer, and then find a way to kidnap a police captain without getting caught. Dexter will also likely try to save Nicky before Aaron kills him, as Dexter has been very disturbed by violence against children. In short, Dexter has quite a bit to do before he can kill Aaron Spencer inDexter: Original Sin.
Dexter: Original Sin
Cast
Dexter: Original Sin explores Dexter Morgan’s early years in 1991 Miami as he transitions from student to avenging serial killer. Guided by his father, Harry, Dexter crafts a moral code and navigates a forensics internship at Miami Metro Police, all while controlling his darker impulses.