​​While there are plenty of familiar faces at Miami Metro in Dexter: Original Sin, some figures from the original series have surprisingly been left out, creating some timeline inconsistencies. The majority of Dexter: Original Sin’s cast of characters is made up of younger versions of figures from the main Dexter series, which include names like Dexter, Harry, and Deb Morgan, Angel Batista, Vince Masuka, and Maria LaGuerta. Since Original Sin’s timeline kicks off in 1991, the prequel highlights some fascinating ways that Miami Metro transforms in the 15 years before Dexter’s series premiere, such as with personnel and procedures.

Miami Metro looks very similar to what it did when Dexter season 1 picked up, but Original Sin still doesn’t have all the major players from that era working with the department yet. For instance, James Doakes isn’t present in Dexter: Original Sin season 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 time Dexter: 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 in Dexter: Original Sin season 1. Captain Matthews (Geoff Pierson) was a significant recurring character throughout Dexter’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 been a colleague and close friend of Harry Morgan prior to the latter’s death.

Since Matthews had already fostered a close bond with Harry before his death, he should already be a fixture at Miami Metro during Dexter: Original Sin season 1’s episodes. Harry dies approximately a year after the prequel’s series premiere, and it’s expected that this moment will arrive during Original Sin’s season 1 finale. Therefore, unless Original Sin is erasing Thomas Matthews’ backstory and deep connection to the Morgan family, there’s no reason for him to still be missing at this point in the story.

Thomas Matthews was the Captain when Dexter season 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 knew the 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 during Dexter: Original Sin season 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 original Dexter series. Given his status as the Captain and a close colleague of Harry Morgan, Spencer is effectively replacing the role that Matthews should have during Original Sin season 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.

Major Dexter Characters Returning In Original Sin

Character
Actor In Dexter
Actor In Original Sin

Dexter Morgan
Michael C. Hall
Patrick Gibson

Debra Morgan
Jennifer Carpenter
Molly Brown

Harry Morgan
James Remar
Christian Slater

Angel Batista
David Zayas
James Martinez

Vince Masuka
C. S. Lee
Alex Shimizu

Maria LaGuerta
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 leaves or 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 during Original Sin’s timeline, his absence – seemingly in favor of Spencer – breaks continuity with Dexter’s main series.

How Thomas Matthews Could Finally Join Miami Metro In Dexter: Original Sin

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 in Dexter: Original Sin season 2, should Paramount+/Showtime choose to renew the prequel. There are a few ways that this could work, but the most prominent theory for Matthews’ arrival claims it will be in response to Captain Spencer leaving Miami Metro in some way. Since there’s no history of Spencer revealed in Dexter’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 exit Dexter: Original Sin is if he’s killed, with some growing fan theories suggesting that he’ll end up being murdered by the same villain 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 to Dexter: Original Sin’s Jimmy Powell case, with Matthews perhaps being introduced as his replacement.