Dexter's Most Memorable Serial Killers

Most people know Dexter Morgan (Michael C. Hall) as TV's most famous serial killer, but he's always held interesting company. After all, how do you root for a protagonist who kills others unless the people he slaughters are worse than he is? Over eight seasons of Dexter, plus the prequel Dexter: Original Sin and two follow-up instalments (Dexter: New Blood and Dexter: Resurrection), there have been plenty of other serial killers who have entered Dexter's orbit. Keep scrolling to see how deeply they affected the titular character and changed his course throughout the franchise. Do you remember them all?

Boyd Fowler (Shawn Hatosy) was a notable member of the Barrel Girl Gang. He was an employee of the Miami-Dade Dead Animal Pickup and was the one who killed and disposed of the women after they were abused by his sicko club. Boyd was one of the few victims who was able to fight Dexter's M99 injection. Dexter eventually regained the upper hand and killed the man, and he became the only member of the Barrel Girl Gang to have a blood slide added to the collection. 

Of all the killers Dexter came up against, Oliver Saxon aka The Brain Surgeon (Darri Ingólfsson) was one of the evilest. Not only was he unstable, but he tortured and tormented his victims, who were often people close to him, like his mother or girlfriend. He also had a significant impact on Dexter when Saxon shot Debra in the stomach. The injury left her brain dead. Eventually, Dex pulled the plug before dumping her body and leaving town permanently.

Some men can't stand powerful women, and Dr. Emmett Meridian (Tony Goldwyn) was one of them. The psychiatrist treated at least three women, whom he talked into taking their own lives by cutting off their medication and filling their heads with suicidal thoughts. Dexter took advantage of the situation for a little free therapy before eventually killing the doc, and learned how to be more intimate with Rita in the process.

Another one of Dr. Vogel's patients, A.J. Yates (Aaron McCusker), had an intricate tech setup in his suburban home, where he kept women captive before breaking each of their toes, killing them, and eventually burying them in his yard under a rosebush. He was initially suspected by Dexter to be the notorious Brain Surgeon, but when he kidnapped Dr. Vogel, the police got involved. Law enforcement, including Dexter and Deb, went to Yates' house to save her. It was there that Dexter realized he was hiding under a bed, and he impaled Yates with a curtain rod before he could attack Debra.

Freebo (Mike Erwin) was a minor drug dealer who killed two women, which put him into Dexter's orbit. However, killing Freebo made things rather complicated for Dexter, as it led to a string of other murders by those looking for the guy. Freebo's murder also led to the short-lived partnership between Miguel Prado and Dexter, as Prado believed Freebo had murdered his brother.

Gareth (David Dastmalchian) is another one of Prater's serial killers, one whose penchant for killing in pairs earned him his astrological nickname. He didn't trust Dexter immediately, but things took a turn in the sixth episode when Dexter killed him. At the next murder club meeting, Gareth showed up. It turned out he had a twin. Dexter took care of that problem too, killing the brother at a Prater gathering by baiting him and pretending it was self-defense. Later, Dexter added the second drop to a blood slide, which he placed in his new trophy box.

King (Jesse Borrego) is remembered for the gruesome way he skinned his victims, hence his nickname. He initially came onto the series as a foil for Debra during an investigation, but when fellow Season 3 villain Miguel Prado tried to set The Skinner on Dexter, the tables turned. King is one of the few villains to kidnap and set Dexter up for a kill. In the end though, Dexter escaped and killed him by snapping his neck in a fight.

Dexter's final love interest (before everything went off the rails with Debra) was Hannah (Yvonne Strahovski), a fellow killer whose life he spared when he realized they had a darker connection. Like Dexter, Hannah's murderous spree stemmed from past trauma. She only poisoned those who wronged her or hurt her, which was something Dexter could relate to. Hannah complicated the relationship between Dexter and Deb when Deb asked him to kill her, which he refused to do. Eventually, Dexter sent Hannah to Argentina to care for Harrison, which she did as his stepmother until her death before the events of New Blood.

When Brian Moser (Christian Camargo) first moseyed onto the scene in Dexter's inaugural season, he did so under the pseudonym Rudy Cooper. At first, he dated Deb, but it turned out he was trying to get closer to Dexter, his biological baby brother. The reveal that his brother also grew up to be a killer was fascinating to Dex, but when Brian insisted on killing Debra, Dexter chose his adoptive family over his blood.

Isaak Sirko (Ray Stevenson) made a mark as the leader of the Koshka Brotherhood in Dexter's penultimate season, but eventually became friends with Dexter. The pair trauma bonded over the loss of their loved ones and need for revenge, helping Dex to feel a little less alone. The connection made Dexter change his mind about killing Sirko in the end, but one of Sirko's colleagues did it instead. In the end, Dexter helped give Sirko a proper send-off, proving that he was still able to connect in a meaningful way.

Joe Jensen (Mike Foy) killed people by burning them alive and leaving a message in the ashes: "Bobby." It turned out Joe was locked up as a child for starting a fire at a school that had been his best friend Bobby's idea. Bobby perished in that fire, but Joe held onto the thought of him for years. When Dexter realized he and Joe had childhood trauma in common, he knocked Joe out instead of killing him, setting him up for the police to find instead.

There's no denying the Barrel Girl Gang was one of the nastiest groups of killers ever featured on Dexter, as they collectively kidnapped and murdered 12 women. At the head of that group was Jordan Chase (Jonny Lee Miller). He was a controlling man who used psychological tactics to torture his victims, which meant he left no physical evidence behind. He still got what was coming to him, though, when Lumen (Julia Stiles) killed him under Dexter's supervision. His death marked the end of Lumen's Dark Passenger, effectively ending her relationship with Dex in the process.

These happily married murderers transported illegal immigrants from Cuba to Miami by boat. However, if the immigrants were unable to pay an extra fee, the couple drowned them and threw their bodies overboard. At first, law enforcement believed the victims had drowned on their own, but when Dexter learned the truth, he took care of both husband (José Zúñiga) and wife (Valerie Dillman).

This New Blood antagonist The Runaway Killer earned his nickname by murdering runaway teenage girls. He lived a double life, however, and as Kurt (Clancy Brown), he was a stand-up Iron Lake community member. When Dexter learned the truth about who Kurt really was, he and Harrison teamed up to end Kurt's life on the kill table. Before his death, Kurt sent a note to Angela implicating Dexter in the murder of his son, Matt Caldwell, which resulted in Dexter's eventual arrest toward the end of the series.

Mia LaPierre (Krysten Ritter) was a famous sommelier, but her true calling was killing. She immediately caught Dexter's eye when he met the fellow serial killers at Prater's dinner party, partially because her reputation was killing sexual predators. However, Dexter quickly realized LaPierre just liked killing in general, and distanced himself from her. Shortly after Mia was arrested for a murder she didn't commit, a guard killed her in prison. Her death hit Dexter hard, and clued him in to the type of power Prater has.

Lila West (Jaime Murray) is one of the most memorable villains from the Dexter universe and a true femme fatale. She met Dexter at a support group, became his sponsor, lover, and eventually, his stalker. Things soured when Lila killed Doakes (Erik King) and kidnapped Dexter's adoptive children, forcing him to follow her to Paris and kill her. Her death obviously ended the love affair, but also solidified Dexter's commitment to Rita.

Few people have had the twisted pleasure of being in Dexter's kill room twice, but Little Chino (former footballer Matthew Willig) is one of them. The gang enforcer escaped the first time Dexter tried to kill him because of his massive size. But Dexter was successful the second time, having learned from his mistakes. To date, Little Chino is the only character to have his cheek sliced twice for those slide trophies. 

After Rita's death in Season 4, the show felt the need to introduce another blonde for Dexter the following year. Enter Lumen Pierce (Julia Stiles), whom Dexter rescued from the Barrel Girl Gang. Lumen was sexually assaulted and tortured, and carried plenty of psychological scars as a result. Eventually, she and Dexter became partners in crime as she sought revenge. They became lovers as well, until Lumen realized her Dark Passenger had disappeared. To date, she is the only living woman in the series who knows Dexter's secret.

Dexter almost made it a decade without bloodshed in New Blood, but then Matt Caldwell (Steve M. Robertson) appeared. The entitled man insisted that Dexter sell him a powerful gun and flaunted his money around briefly before killing a white stag Dexter had been seeing around. The fresh bloodshed, coupled with information that Matt was responsible for the deaths of five people, awakened Dexter's Dark Passenger and he slaughtered Matt in response.

When Assistant District Attorney Miguel Prado (Jimmy Smits) revealed he knew about Dexter's Dark Passenger, it seemed like a potential dream team in the making. Having someone to share his dark secrets with was a temporary relief for Dexter. But when Prado began breaking the code, pushed for more power, and targeted LaGuerta, it was only a matter of time before he landed on the kill table. Dexter realized he wasn't a partner kind of guy in the process, despite having thought he'd finally found a real friend.

Before Dexter homed in on his Dark Passenger code, he began his spree with a character named Nurse Mary (Tanya Clarke). This Angel of Death came into Dexter's orbit when she began poisoning Harry (Christian Slater) in the hospital following a heart attack. Upon further investigation, Dexter realized she was a killer, and she became his first official victim.

On the surface, Al Jolly (Eric Stonestreet) is a family man and loving father. When he goes on his business trips, though, he becomes serial killer Rapunzel, who strangles his victims and cuts off their ponytails as trophies. In Dexter: Resurrection, Rapunzel is one of the serial killers collected by Leon Prater (Peter Dinklage), and Dexter interacts with him under false pretenses, as a serial killer named Red.

As the original Dexter continued into its later seasons, the killers seemed to become more demon-like. Killers like Ray Speltzer (Matt Gerald), who constructed mazes and chased his victims while wearing a minotaur mask before beating them to death. Ray captured Dexter and threw him in the labyrinth, but Dexter outsmarted and killed him. He burnt the body and his blood slide collection with it, but the death was also significant because it was the first stalk and kill that Dexter involved Debra in.

Ronald Schmidt's (Marc Menchaca) nickname was a large part of why Dexter returned to the killing scene in the latest franchise installment. Dexter realized his legacy still mattered to him, and he had already claimed The Dark Passenger for his urges long ago. So, he resurrected the kill room and went back to his old ways. Ronald, or "Red" as Dexter called him, was integral to the setup of Resurrection in a bigger way: He became the guy Dexter impersonated to find out what Prater's murder club was all about.

Dexter first met Lowell (Neil Patrick Harris) at Prater's house during his meeting of the serial killer minds. Dexter was undercover as The Dark Passenger and didn't seem to think much of Lowell until he revealed he was about to make his next kill — and preserve the tattooed flesh. Naturally, Dexter couldn't have that, so he made his move and killed Lowell instead. The moment marked Dexter's commitment to taking down serial killers, even if he now dined among their ranks.

The series didn't often mix religion into its murders, but when Travis Marshall (Colin Hanks) popped up, that all changed. Travis committed biblical-themed murders, viewing his victims as sacrifices and part of God's plan to bring on the End of Days. He also had mental health issues and even tried to sacrifice Dexter's son. That didn't sit well with Dexter, and he strapped Travis to a kill table at a church. What Dexter didn't count on was Debra witnessing the act and learning her brother's true nature in the process.

Arthur Mitchell (John Lithgow) remains one of the most memorable serial killers ever featured on Dexter, and for good reason: He is the reason Dexter lost his wife and the mother of his son. After Dexter began pursuing Arthur, the Trinity Killer (who killed in fours, not threes) tracked him down and killed Rita (Julie Benz). It was a horrifying twist, and Harrison was there, continuing the born in blood cycle that eventually breathed new life into this franchise.

Before Dexter was teaching the Code of Harry to Harrison, he was bonding with a young killer named Zach Hamilton (Sam Underwood). The son of a rich friend of Miami Metro, Zach paralleled Dexter in multiple ways and became a son figure to the killer. The relationship was short-lived, however, when The Brain Surgeon put a gruesome end to Zach's life.