WARNING! This article contains SPOILERS for Dexter: Original Sin season 1, episode 5!While there are plenty of familiar faces at Miami Metro inDexter: Original Sin, some figures from the original series have surprisingly been left out, creating some timeline inconsistencies. The majority ofDexter: Original Sin’s cast of charactersis made up ofyounger versions of figures from the mainDexterseries, which include names like Dexter, Harry, and Deb Morgan, Angel Batista, Vince Masuka, and Maria LaGuerta. SinceOriginal Sin’s timeline kicks off in 1991, the prequel highlights some fascinating ways that Miami Metro transforms in the 15 years beforeDexter’s series premiere, such as with personnel and procedures.
Miami Metro looks very similar to what it did whenDexterseason 1 picked up, butOriginal Sinstill doesn’t have all the major players from that era working with the department yet. For instance,James Doakes isn’t present inDexter: Original Sinseason 1, though he could eventually make an appearance in the series’ future.More curious, however, is the absence of Captain Thomas Matthews, who should already have an established role at Miami Metro by the timeDexter: Original Sin’s story begins.

Captain Thomas Matthews Should Already Be At Miami Metro In Dexter: Original Sin Season 1
Matthews Was A Close Friend Of Harry’s On The Force Before His Death
Oddly, a younger Thomas Matthews isn’t working at the Miami Metro Police Department inDexter: Original Sinseason 1. Captain Matthews (Geoff Pierson) was a significant recurring character throughoutDexter’s original eight seasons, appearing in all but season 3. Not only is Matthews the police captain when the original series begins, but he had also been working at Miami Metro for years by that time, having beena colleague and close friend of Harry Morgan prior to the latter’s death.
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Since Matthews had already fostered a close bond with Harry before his death, he should already be a fixture at Miami Metro duringDexter: Original Sinseason 1’s episodes. Harry dies approximately a year after the prequel’s series premiere, and it’s expected that this moment will arrive duringOriginal Sin’s season 1 finale. Therefore,unlessOriginal Sinis erasing Thomas Matthews’ backstory and deep connection to the Morgan family, there’s no reason for him to still be missingat this point in the story.

Thomas Matthews was the Captain whenDexterseason 1 began, but he was promoted to Deputy Chief in season 6.
Regardless of what position Thomas Matthews had at Miami Metro in 1991, he should already be on the force and working closely with Harry. Indeed, the two were so close that Matthews was one of the few people who knewthe truth about how Harry Morgan died; while Dexter and Deb were told that their father died from heart disease, he had actually died by suicide after overdosing on his heart medication.Before his death, Harry asked Matthews to keep an eye on Dexter and Debra, and Matthews stayed true to his promise throughout the original series.

Did Dexter: Original Sin Replace Thomas Matthews' Character With Aaron Spencer?
Aaron Spencer Is The Captain Of Miami Metro Homicide During Dexter: Original Sin Season 1
Rather than Matthews,the Captain of Miami Metro Homicide duringDexter: Original Sinseason 1 is Patrick Dempsey’s Aaron Spencer. Dempsey’s character is a brand-new figure crafted for the prequel, and wasn’t mentioned at all during the originalDexterseries. Given his status as the Captain and a close colleague of Harry Morgan, Spencer is effectively replacing the role that Matthews should have duringOriginal Sinseason 1. Even if Matthews was only a Lieutenant at this time, the general story function of his character is still being served by Spencer instead.
Lauren Vélez
Christina Milian
That said, it’s unclear whether Captain Spencer’s role is meant to erase Thomas Matthews from this era of Dexter’s life entirely. Rather,Spencer could simply be the Captain during season 1, with Matthews potentially arriving at the station after he leavesor is dismissed. Matthews and Spencer also don’t have the same backstory, with Matthews’ wife having died while Spencer is divorced. Still, even if Matthews was at a lower rank duringOriginal Sin’s timeline, his absence – seemingly in favor of Spencer – breaks continuity withDexter’s main series.
Matthews Could Replace Spencer If He Leaves Miami Metro
Image via Paramount+
Even though Thomas Matthews isn’t in season 1, there’s always the possibility that he could arrive inDexter: Original Sinseason 2, should Paramount+/Showtime choose to renew the prequel. There are a few ways that this could work, butthe most prominent theory for Matthews’ arrival claims it will be in response to Captain Spencer leaving Miami Metroin some way. Since there’s no history of Spencer revealed inDexter’s main series, there are several ways in which he could exit the show – some of which would be quite tragic.
One way that Captain Spencer could exitDexter: Original Sinis if he’s killed, with some growing fan theories suggesting that he’ll end up being murdered by the samevillain who killed Jimmy Powell. Alternatively, another less likely theory speculates that Spencer himself is secretly the killer, and will end up on Dexter’s table. There’s also the possibility that Captain Spencer resigns or is let go from Miami Metro for a reason related toDexter: Original Sin’s Jimmy Powell case, with Matthews perhaps being introduced as his replacement.

New episodes ofDexter: Original Sinseason 1 release Fridays on Paramount+ with Showtime.
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.
Dexter
Dexter is a television series following Dexter Morgan, a blood spatter analyst for Miami Metro Police who secretly leads a dual life as a vigilante serial killer. Released in 2006, the show focuses on Dexter’s internal conflict as he hunts down criminals who elude justice within the legal system.
