Dexter was ultimately the story of a man looking to find connection anywhere he could, but it was driven by the very compelling premise of a serial killer who only targeted other serial killers. Raised on “Harry’s Code” by his foster father, Dexter Morgan grows up blood hungry, but only for a very specific type of person.
Over the course of Dexter’s 8 seasons, Miami Metro’s titular blood spatter analyst finds himself coming face to face with some of the nastiest killers on television. For as sub-par as Dexter could get in its later seasons, it at least always knew how to introduce interesting serial killers into the mix. Worth noting, characters like Miguel Prado and Isaak Sirko are not serial killers. Miguel, while trained by Dexter, only manages to kill two people, whereas Isaak, who kills over three, has no consistent MO across his killings nor does he resemble a serial killer in either the context of real life or Dexter.
The Brain Surgeon
On paper, the Brain Surgeon isn’t a bad concept for a serial killer. Oliver Saxon is meant to be the closest mirror to Dexter there is– a representation of what Dexter is when we strip him away of his protagonist status. But there are fundamental issues rooted in Oliver’s character. For starters, he’s a brand new villain introduced in the final season and he isn’t even the final villain– Elway is.
Worse, he spends half the season acting like a worse version of the Ice Truck Killer, trying to play games with Dexter and Dr. Vogel that frankly lead nowhere meaningful or memorable. That Dexter deals with Saxon so effortlessly just highlights how one note the Brain Surgeon really was.
The Skinner
Speaking of one note, the Skinner is the worst serial killer to come out of the first few seasons. For whatever reason, the writers felt Dexter needed to go up against a traditional serial killer amidst his friendship with Miguel in season 3. George King is at the very least built up all season in a way that makes enough sense, but he’s such an unremarkable character.
The reveal that he’s the Skinner is worthless, and he spends all season consumed by a storyline we as an audience know is going nowhere. That’s part of the dramatic irony of his killings– he will never stop because he will never find Freebo– but beyond his gruesome manner of killing people (including the skinning of a child,) there’s little to appreciate about the Skinner.
The Poisoner
All of Dexter’s love interests who aren’t named Rita are controversial in their own ways, but Hannah McKay tends to be the most outwardly reviled, in large part due to her character assassination in season 8 (with no other seasons aside from the seventh to get a feel for her.) That said, season 7 establishes her as fairly competent.
She ends up showing Dexter how life with a serial killer is inherently built on mistrust. Through Hannah, the audience can piece together & understand why Deb’s faith in Dexter has been totally shattered come season 7. Hannah’s “survival of the fittest” mentality keeps her alive and active better than most killers in the series, but given how season 8 leaves off (and how her character is written,) it’s unlikely she’ll be around much longer.
The Barrel Girl Gang
A mix of serial rapists and killers, the Barrel Girl Gang was comprised of leader Jordan Chase and his lackeys Boyd Fowler, Dan Mendell, Cole Harmon, and Alex Tilden. The men are responsible for the rape and murder of over a dozen women, and Dexter teams up with Lumen to take them out– stemming from his guilt over Rita’s death and a blossoming midlife crisis.
None of the Barrel Girl Boys are particularly compelling villains on their own, but Boyd Fowler and Jordan Chase are fairly interesting characters who develop interesting relationships with Dexter. Jordan himself is even set up as a physical powerhouse of sorts, contrasting him with previous serial killers, but beyond his manipulation, Dexter & Lumen take him out no worse for wear.
The Doomsday Killer
Originally believed to be Professor James Gellar, the Doomsday Killer was a biblically inspired killer whose killed were tableaus in reference to passages from the Book of Revelation, the final book in the New Testament. As the Book of Revelation chronicles the apocalypse, the Doomsday Killer’s intent is to trigger the end of the world with his ritualistic killings.
Ultimately revealed to be shunned student Travis Marshall, tension with the Doomsday Killer comes not from him trying to end the world, but the extremes he goes to. He very nearly manages to kill Dexter, and he even abducts Harrison for his final tableau. Dexter kills Travis in the end, but even his death ends up resulting in Dexter getting caught by Deb in the act. Travis may not be the most beloved serial killer in the series, but there’s enough compelling about him.
The Ice Truck Killer
The first major serial killer Dexter squares off against (in the TV series at least,) the Ice Truck Killer ends up having a very intimate connection to Dexter’s past, one that ensured Dexter could grow as a character while the story developed alongside him. Dexter’s biological brother, Brian Moser uses his killings as a means of reconnecting with Dexter.
What Brian wants more than anything is to break away Dexter’s code. As a serial killer, he’s fairly successful, draining his victims and leaving little trace. Unlike Dexter who hides all evidence anyone was ever killed, Brian instead revels in his killing– putting them on display for the world to see. Dexter takes him out, but the Ice Truck Killer’s presence is felt across the entire series.
The Bay Harbor Butcher
Good old Dexter Morgan himself. It’s kind of hard to believe he gets away with it all, especially considering how often he does get caught. Still, when push comes to push, Dexter is always able to dig himself out of a hole. It’s hard to discuss his arc as a serial killer without mentioning the lousy series finale, but it’s worth noting that speculation states a large percentage of active serial killers are long haul drivers– not unlike what Dexter is in the finale.
He not only gets away with it, Dexter is likely still killing. On the flip side, this ending can also be read as the rather straightforward, “Dexter’s killings catch up to him and he finally does the responsible thing and detatches from society.” Either way, the Bay Harbor Butcher gets away with everything.
The Trinity Killer
But he doesn’t get to have a life. Early in season 4, Dexter describes the Trinity Killer as the most successful serial killer who got away with it. For decades, Arthur Mitchell kills in threes (actually in fours, meaning he’s killed even more people than Miami Metro initially realizes,) and he’s done so without ever falling on anyone other than Lundy’s radar– who can’t even prove the killings are connected or that the killer exists at first.
Dexter has multiple opportunities to kill Arthur Mitchell, but squanders them each and every time. By the time Dexter finally gets his chance, it’s too late. Arthur outplayed Dexter and murdered his wife, Rita. When Dexter returns home after killing Trinity, he finds his son born in blood. The Trinity Killer won.
