In September of 1982, an unidentified sociopath somewhere in Chicago became the star of every evening news broadcast after they replaced the contents of eight bottles of Tylenol with goddamn cyanide, causing several people to keel over and die from apparent massive heart attacks. In at least one case, to relieve the stress headache caused by lamenting the death of a loved one who'd consumed poisoned Tylenol, a victim's family member died from taking the same poisoned Tylenol.
Altogether, the poisoned bottles of headache powder killed seven people, triggering a massive recall of 31 million bottles, all of which were presumably thrown into the sea. The subsequent investigation determined that the poisoning occurred after the bottles left the factory ... and that's pretty much all we know. Tylenol offered a massive reward for information about the culprit, but all they ever got was a guy pretending to be the killer so he could collect the reward from them -- a plan that was as flawed as it was douchey.
It was a major headache for all involved.