What exactly is a serial killer? Dexter doesn’t go into the specifics too often, but a serial killer is someone who has killed three or more people in a specific time gap (typically within a month), in order to satisfy their psychological urges. Reading all this out, Dexter Morgan is a textbook example of a serial killer, and he’s one of the most prolific in television history.
But he’s not the most prolific, nor does he leave his mark alone. Dexter featured many serial killers over its eight-season run, and not each one managed to end the season with as impressive a kill count as the Bay Harbor Butch. In truth, few can compare to the bodies in Dexter’s wake, but that in itself is interesting to note in the context of the series. Dexter’s villains haven’t killed nearly as much as Dexter.
The Skinner (3 Confirmed Kills)
The Skinner is the only serial killer on this list who is not a major character at any point within the series. He’s the main serial killer active during season three, but ADA Miguel Prado is the season’s actual antagonist, with the Skinner ultimately just wrapping up Miguel’s loose threads come the finale.
Over the course of the season, the Skinner wracks up three kills—just enough to be considered a serial killer in the eyes of Miami Metro. His life as George King strongly suggests that the Skinner had a higher body count, but, as far as his skinnings go, King just barely makes the cut—no pun intended.
The Poisoner (7 Confirmed Kills)
Hannah McKay is never referred to as The Poisoner in-universe, but title consistency matters, and it’s also just worth noting her method of serial killing. Whereas just about every other major serial killer in the series makes their killing a ritualistic act which demands face to face interaction, Hannah abides by the rules of “survival of the fittest.”
Hannah kills quietly, leaving effectively no trace in her path. She’s one of Dexter’s most interesting foils (in season seven, and only in season seven,) with her method of killing especially unique after six seasons strait of bloody murder. Still, coming in so late in the series means Hannah can only kill so many people on-screen, leaving her with a comparatively low confirmed kill count.
The Doomsday Killer (11 Confirmed Kills)
Originally believed to be a former Professor of Religious Studies at the University of Tallahassee, Professor James Gellar, the Doomsday Killer turns out to be none other than Travis Marshall, a young man Dexter tried to squeeze the Dark Passenger out of. Travis’ killings are all biblically inspired, specifically using the Book of Revelations as an inspiration point.
Travis believes that by completing his “tableus,” he’ll be able to end the world in a biblical apocalypse. Dexter ultimately stops him, but it’s worth noting that Travis only manages to end up with 11 kills, one shy of 12—an important number in Christianity. Beyond the number 12 appearing multiple times in symbolic roles across both the Old and New Testament alike, the Book of Revelation alludes to the number 12 constantly. It’s fitting Travis falls just one killing short.
Barrel Girl Gang (13 Confirmed Kills)
Responsible for the rape and murder of 13 confirmed women, the Barrel Girl Gang were comprised of Boyd Fowler, Dan Mendell, Cole Harmon, Alex Tilden, and motivational speaker Jordan Chase. While Jordan himself does not physically rape or murder the women (until later), he is directly responsible for the rest of the gang doing so, arranging these kidnappings and murders as a means of getting the other men to reconnect with their “primal self.”
Each member of the gang is ultimately systematically killed one by one courtesy of Dexter and Lumen. Jordan Chase specifically stands out as the only main antagonist to never kill more than one person on-screen.
The Brain Surgeon (16 Confirmed Kills)
The series’ final antagonist, and by far the worst, Oliver Saxon is introduced in season eight as the “truest” mirror to Dexter. Oliver is supposed to represent everything Dexter was before he started developing emotions (ignoring the fact Dexter always had emotions). Oliver takes a very “game-like” approach to Dexter, not too dissimilar to the Ice Truck Killer, leaving his companion clues along the way.
Unlike The Ice Truck Killer, however, the Brain Surgeon is content letting others do his dirty work. His confirmed kill count is befitting for a final antagonist, but his role in the story is ultimately remarkable, and he’s so non-present in his own season that there isn’t much of substance to discuss outside of his weak thematic connections to Dexter.
The Ice Truck Killer (19 Confirmed Kills)
The first major serial killer Dexter faces off against in the television series (but not chronologically as per the mini-series Early Cuts), the Ice Truck Killer is none other than Dexter’s biological brother, Brian Moser. Brian drains his victims of all their blood–a perversion of Dexter’s infatuation with blood—while trying to reconnect with his long lost little brother all season.
The Ice Truck Killer is one of the more gruesome serial killers in the series, if only because of how in control he’s in for so long. Of course, this stems from Dexter trying to find Brian before Miami Metro, but the Ice Truck Killer stands out as one of Dexter’s most successful serial killers—third place, in fact, which makes Brian’s 19 kills quite funny when we jump to Dexter.
Bay Harbor Butcher (135 Confirmed Kills)
To be fair, the Ice Truck Killer almost certainly has more than 19 kills total, but 19 is all we can glean from in-text evidence. Dexter, on the other hand, sits at a towering 135 kills come the series finale. It only makes sense. As Dexter is the main character we follow—and the series ran eight seasons—all those kills added up.
Plus, this is to say nothing of the fact Dexter tends to kill in-between seasons whenever he can. Worth noting, Dexter ends the series finale not necessarily a lumberjack, but as a long haul truck driver. It’s speculated that a large percentage of currently active serial killers are long haul drivers. Realistically, Dexter’s kill count didn’t really cap off at 135.
Trinity Killer (279 Confirmed Kills)
Including both his cycle and non-cycle killings, the Trinity Killer, a.k.a. Arthur Mitchell, dies with a staggering 279 confirmed kills under his belt. It’s even possible he’s killed more than just that, but that’s as far as the Trinity Case investigation gets us. Dexter notably refers to the Trinity Killer as the most successful serial killer who got away, and he’s right.
In more ways than one, too. While Trinity’s 279 confirmed kills speak for themselves, Dexter’s correct about Arthur narratively when all is said and done. Although Dexter does ultimately kill him, Arthur had killed Dexter’s wife, Rita, beforehand. In the end, the Trinity Killer really did get away with everything, and Dexter even deprived Miami Metro the chance of catching him.
