As soon as he got out of jail, Haigh put his spectacularly flimsy theory to the test by murdering several wealthy business owners, drinking a teacup of their blood (in addition to being stupid and lazy, Haigh was also as daffy as a shithouse rat), and dissolving their remains in acid and pouring them down the bathtub drain. After the deed was done, he would use his skills as a forger to take over his victims' businesses, using their personal wealth to finance his suddenly high-class lifestyle of fast cars, expensive hotels, and incredibly strong bathtubs.

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60 percent porcelain, 40 percent entrails

In spite of Haigh's unconventional source of tremendous income, he was still spending more than he was making, and he had to keep melting rich people to make ends meet. He'd drank at least six teacups of blood and dumped as many bodies into acid before the police finally noticed a connection between all the missing upper-class and Haigh's rapidly growing wealth, and they arrested the shit out of him.

During his interrogation, Haigh predictably resorted to his "if there's no body, there's no murder" defense, to which the police offered the powerful rejoinder, "That's not what corpus delicti means, dumbass." Despite his ghoulish body-disposal strategy, Haigh had kept more than enough of his victims' personal belongings to put his head in a noose. We assume they also put a stake through his heart and buried him in a ring of salt just to be sure.

Souza, a former police officer, was the host of Canal Livre, a Hard Copy-type show that was hugely successful due in no small part to the fact that they always seemed to get their hands on exclusive footage of grisly crime scenes. In fact, not only did Souza's camera crews beat rival TV shows to the scene of outrageous crimes, they often arrived before the police did. As you might imagine, the police found this suspicious.

Realistically, there were only two possible explanations for Souza's crews getting the scoop on these crimes so quickly -- either Souza had an inter-dimensional psychic on his payroll, or he had some inside knowledge of the killings. The cops went with the latter and began investigating Souza's precognitive television program. They arrested a former bodyguard who claimed that he had committed at least one brutal murder at Souza's request so that it could be covered on Canal Livre, and when they raided Souza's house, they discovered he owned more assault rifles than pillows.

AP
They couldn't just arrest him, though. First, they had to remove him from the state senate.

Souza turned himself in, protesting his innocence and insisting he'd been framed by one of his rivals, presumably Dennis Farina from Unsolved Mysteries. Unfortunately for justice, Souza was hospitalized with liver disease shortly after his arrest and died before he could go to trial, so the circumstances behind his criminal enterprise remain unresolved. One can only imagine the ratings boost he would have received reporting on his own trial.

That brings us to Elmer Wayne Henley, who was a struggling high-school dropout in the 1970s trying to make ends meet. Because he was something of an unscrupulous fellow, he and his friend David Brooks began working for a local candy store-owner named Dean Corll, but not stocking the shelves or reordering Twizzlers -- Corll had a thing for killing teenage boys, and Henley's job was supplying him with victims.

You see, Corll realized there were easier ways to procure victims than skulking around the neighborhood in a ski mask, and was apparently blind to the irony of the fact that he owned a candy store, so he outsourced his stalking to Brooks, who brought Henley in on the deal. In all fairness, at first Henley didn't know Corll intended to murder the teenage boys he was rounding up -- he was under the impression that Corll was merely running a sex-slave trade. Also, Corll was paying him $200 per victim, so Henley wasn't interested in digging too deep. And $200 in the '70s was like $400 in the '90s, which means he was trading these people for the equivalent of two brand-new Super Nintendos -- more than enough to make a teenage burnout look the other way.

Houston Chronicle
"Plus the victims get free candy, so lucky them." -Henley, probably.

Over the next three years, Henley and Brooks supplied Corll with 27 youths that we're aware of. It eventually got to the point where Henley was selling his own friends to the Candy Store Murderer to finance his recreational drug habit, because friendship is nice, but drugs and money are drugs and money.

Their arrangement came to an abrupt end when Henley made the mistake of bringing a girl to a paint-huffing party at Corll's house. Corll freaked out and tried to kill everyone in the room, but Henley managed to get Corll's gun away from him and shoot him.

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This made him a model citizen, just like Dexter.

Although he was initially treated like a hero, things changed when Henley idiotically mentioned to Tim Kerley, one of the people he'd just rescued, how much money he could have made selling Kerley to Corll instead of saving him. Kerley understandably found this statement to be thunderously suspicious, so he informed the police, who quickly unraveled the long-standing business arrangement between Corll, Brooks, and Henley. The two teenagers were rewarded with life sentences, a phrase here meaning "decades of regret over not just getting a job at Burger King."

Mullowney was so good at priest eradication that he wound up with a price on his own head, because when your job consists of decapitating Catholic clergymen in Ireland, it makes you unpopular with everyone except the bartenders. He was eventually caught by a mob of outraged locals, who killed him and tossed his body into a lake. Considering his reputation, we wouldn't be surprised if he faked his death so that he could leap out of his coffin during his funeral and claim one final bounty.

via Irish Gravs
R.I.P. Sean na Sagart. Your soul now rests where no priests dwell.

Palmer's plan was embarrassingly straightforward. He began taking out bloated insurance policies on his various relatives and acquaintances, and then slowly poisoning them to death to collect the money. All told, he is believed to have killed around 15 people, including his wife, mother-in-law, and so many of his children we're amazed he was a real person and not a character in a Roald Dahl novel.

Eventually, the insurance companies (not the police) began to wise up to the fact that everyone Palmer took a premium on had a tendency to drop dead, and after his brother died, they refused to pay. Undeterred, Palmer switched targets to his pal John Cook, who actually survived Palmer's first murderous attempt. Despite literally telling people, "I believe that damn Palmer has been dosing me," Cook continued to hang out with Palmer until the doctor succeeded in poisoning him with a bowl of soup. Palmer was so bad at clandestine murder he was like a lazily written episode of Law & Order.

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But an unusually riveting episode of Iron Chef.

The police finally decided enough was enough, and Palmer was arrested and subsequently hanged for the ridiculously brazen killings. The mad doctor had become so infamous that the people of Rugeley were concerned their town would always be associated with him, so they approached the prime minister to request they be allowed to change the town's name. The prime minister agreed, on the condition that they rename the town after him. Unfortunately, the PM's name happened to be Lord Palmerston, so the townspeople wisely decided to stick with Rugeley.