Upon further examination, it turned out the victims had all fallen for the same scam -- they found unopened drinks inside the machine's dispenser slot, presumably left there by the last person, for whatever reason. Since the human brain tends to shut down all further thought upon the discovery of free s**t, they scarfed down the prized beverage ... then quickly regretted it. The poison was so effective that victims would often start to feel sick before they had finished their drink. We're guessing they still finished it, though, because hey, it was free.

To be fair, there was actually another, ingenious layer to the poisoner's strategy: The product most often tainted was a Japanese energy drink called Oronamin C, which was running a promotion whereby vending machines would occasionally dispense a bonus second drink. It wasn't hard to imagine that some customers were walking away without realizing that a second drink was rolling down the chute, a phenomenon that the killer was taking full advantage of -- the unsuspecting victims had even less reason to be wary.

Otsuka Pharmaceutical Co.
Being sold a brutal, unforgiving onslaught of cute-n-quirky probably didn't help either.

Here's where we'd love to tell you all about the psychopath who hatched this scheme, and their method, and why they did it. Too bad -- nobody f*****g knows. A serial killer who took a dozen victims (that we know about!) and could have had three dozen more if they'd ingested more of the toxin and/or didn't get help in time, may still be out there today. s**t, for all we know, only the first couple were this guy and the rest were copycats (which would actually be even more alarming, the idea that it just became a fad).

After they figured out what was happening, the vending machine company began attaching stickers to the machines that warned customers not to, you know, consume mystery drinks that they might find inside. The poisonings pretty much stopped overnight. Which is great, except that any leads the police might have had in the case dried up as well. No arrests were ever made, which means that there's probably some guy in Japan right now chugging a bottle of Oronamin C and musing on his brief serial-killing hobby. Or, you know, he's still killing people using some other method.

Christina Chun/Honolulu Star-Advertiser
Keep him away from any and all jars of Kit-Kats.

Since 1975, the bodies of at least 30 women have been found dumped in fields near Edmonton, Alberta, Canada, some of them burned to death. Unfortunately for their families and loved ones, many of the victims were sex workers, and many of them Indigenous -- two factors which, depressingly, mean that the police will prioritize your murder investigation somewhere between "truancy" and "cat up a tree."

Project KARE
We're not detectives, but maybe once you hit double digits you should bump it up on the to-do list?

But after 40 years and dozens of victims, the Canadian police have been forced to conclude that they might have a serial killer on the loose. It's either that, or several killers in the area have all landed on the exact same modus operandi (again, would you prefer it be one guy, or some kind of murderous cult?). Nevertheless, police are pretty much stumped, knowing nothing about the killer except that he probably drives some sort of truck, feels comfortable with rural driving, and enjoys outdoor activity, which narrows the possibilities down to like 80 percent of the entire Canadian male population.

That's not to say they haven't been doing anything -- in 2003, they set up Project KARE, a task force dedicated to fighting back against the serial killer, mostly by maintaining a database of DNA samples from local sex workers. You know, so that they can identify the corpses.

Royal Canadian Mounted Police
It's all part of their never-ending quest to do at least one part of their job well.

Oh, but did we mention that they actually have the killer's voice on tape? In 2010, one of the victims, Amber Tuccaro, made a phone call to her brother while she was hitching a ride with a man whose voice can be heard on the tape. Since her time of death is estimated to be around the time the call ended, it can be pretty safely assumed that this man might have had something to do with it.

The police waited two years to release the recording, and since then, at least three women have come forward to report that they know who the guy is. We're sure they're about to make an arrest any day now -- remember they only got that recording, uh, six years ago.

The killer started his spree by murdering Robin Fuldauer in a shoe store that she was managing. His second and third victims, Patricia Smith and Patricia Magers, were killed in their bridal store, most likely because he didn't know there were two people present. McCown was next, killed in his ceramics store, and two more murders followed -- Nancy Kitzmiller, in another shoe store, and Sarah Blessing, in her gift shop. After that, the killings stopped.

The Witchita Eagle
We usually encourage people to never give up on their dreams, but in this case, we're glad he did.

The thing is, the I-70 killer wasn't exactly your Hannibal Lecter-tier serial killing genius. In fact, he was sloppy as hell -- he killed in public and in broad daylight, and there are so many witnesses to his crimes that they could start a local book club. After he killed the two Patricias, one witness saw him so clearly that he was able to provide a composite sketch. Another witness saw him enter the scene of his final killing, and still more saw him leaving the scene as he rushed back toward the I-70.

But despite a whole bunch of people knowing exactly what he looks like, and the fact that his face has been plastered over true crime shows over the last 20 years, no suspects have ever been identified. We guess he just has one of "those faces."

One suspect, retired police officer Jairo Francisco Franco, was ultimately charged based on a witness report -- they claimed he was the one who shot the guy 12 times -- and the fact that by having three names, he met the first requirement for becoming a famous murderer. He went to trial and after two-and-a-half years of criminal proceedings, he was found not guilty.

TViG
He was presumably stripped of his third name to cut down on any future mix-ups.

But, even if he had been convicted, the shooting he's accused of is one of the odd ones -- it could have turned out he did that one, and not the rest of the ritualistic "one shot to the head" executions. Either way, no further arrests were made.

The good news is the killings also stopped. You could say this proves it was Franco but, then again, the arrest could have convinced the real killer the cops were getting too close. Either way, somebody got away with it, scot-free.

In the late 1960s, women starting vanishing from the Barrowland Ballroom, a nightclub in Glasgow, Scotland. Between 1968 and 1969, 25-year-old Patricia Docker, 32-year-old Jemima McDonald, and 29-year-old Helen Puttock were all murdered after nights out at the Barrowland. All three were strangled with their own stockings, and all three women's handbags were missing, most likely taken as a souvenir. Yep, sounds like a serial killer.

Over the years, these killings have blown up into one of the biggest crime investigations in Scottish history. And this is despite the fact that, just, so many witnesses know exactly what he looks and sounds like.

Grampian TV
"Start extradition papers for Ron Howard ASAP."

These were all nightclub hookups, after all, and the victims all had friends who saw who their buddy was going home with; they even shared a cab with him in at least one instance. In most cases, the killer identified himself as John, and was notable for constantly quoting from the Bible, which gave him his media nickname "Bible John." s**t, if he was any more of a serial killer, he'd turn up to the club wearing someone else's face.

Grampian TV
There's a lot of Bible to cover, so maybe he never read the "don't kill" part.

Despite knowing so much about what Bible John looked like that they were able to plaster his portrait all over the Glasgow night scene, and putting cops undercover all over the damn place, they still never caught the guy. They did identify one suspect in 1996, John McInnes, who unfortunately couldn't answer any questions due to the fact that he'd been dead for 16 years. But, after exhuming his corpse, they ultimately proved he wasn't the guy, and had to apologize to his family for digging up his skeleton and calling it a serial killer.

Grampian TV
"We took it by his silence that he was cool with it. Our bad."

Since then, the case has gone drier than John McInnes' bones, and at this point it's unlikely that Bible John will ever be found, considering that he's probably in a retirement home, if he's alive at all (at the very least, his clubbing days are probably behind him). Or, maybe he got arrested for some other crime decades ago. Or, maybe his last victim managed to kill him in self-defense, and nobody ever found him. Make up whatever story you want, because we'll never know the truth. Sometimes, that's just the way it goes.

Janel Comeau is not a serial killer, but you should probably keep an eye on her on Twitter and her blog, just in case.

For more stories to keep you up at night, check out 5 Horrific Serial Killers (Who Are Free Right Now) and 5 Real Killers More Terrifying Than Any Horror Movie.

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