One of the longest-running theories is whether Matthews was aware of Dexter's secret.
If we go back to the original Dexter series, one of the strongest and most popular fan theories that still holds up today revolves around Tom Matthews. Even though he was never a central figure and only became a series regular in the final season, there was always something about him. The way he carried himself and the subtle writing around his character made fans believe he knew about Dexter’s secret.
And to be fair, there were plenty of moments that actually fed into that idea. But beyond that, fans took it a step further and believed he was actively protecting Dexter. A big part of that theory comes from his close relationship with Harry Morgan and the loyalty he had for him, which for a lot of viewers, made perfect sense that Matthews would look the other way if he ever figured out who Dexter really was.
Season 7 is usually where this theory actually peaks. That is when the Bay Harbor Butcher case comes back into focus after Maria LaGuerta discovers the blood slide at Travis Marshall’s crime scene. From that point on, suspicion began circling back to Dexter, and Matthews (who at this point was no longer part of Miami Metro) consistently shuts LaGuerta down.
He dismisses her theories, sometimes even mocks them, especially when they point toward Dexter. For us fans, that actually felt intentional, like he was stepping in to protect him without making it obvious.
But is that really the case? According to Geoff Pierson, not really. In a recent interview with Brett Allan, he shared that based on how the original series played out, Matthews didn’t know about Dexter, mainly because it was never directly addressed. At the same time, he clealry understands why fans see it differently. As he put it, “As it turned out, I didn’t know, but I think the audience figured I knew, and I was in some ways protecting him.”
So...while Pierson acknowledges the theory (and even the logic behind it) he actually leans toward the idea that Matthews was not really written as someone who knew. Still, the fact that it was never confirmed either way is exactly why this theory hasn’t gone away.
Now, with Dexter: Resurrection continuing the story, there is a real chance this could finally be addressed. The revival has not shied away from revisiting old characters, and after what we’ve actually seen with Batista, it’s clear the door is open, and Matthews could definitely walk back in one way or another.
It is worth noting that during the same interview, Pierson also mentioned that he hasn’t watched Dexter: New Blood, Dexter: Original Sin, or even Dexter: Resurrection Season 1, and wasn’t asked on whether he would like to return.
So nothing is confirmed on that front. But honestly, with the way things are going, this is definitely the perfect opportunity to bring him back. With Batista, Masuka, and Quinn already returning, Matthews showing up again, especially if it means finally answering this long-running theory, would absolutely fit right in.