It was raining in Pasadena, Texas, on Halloween night 1974. But local children swarmed the streets regardless, buoyed by the promise of lollies and chocolates held behind decorated doors.
Among those trick-or-treating were eight-year-old Timothy O'Bryan and his five-year-old sister, Elizabeth, accompanied by their optician father Ronald Clark O'Bryan. The family were from nearby Deer Park, but had arranged to join a friend from church, Jim Bates, and his two young children, in their more affluent neighbourhood.
The group approached a darkened house and knocked. When no one answered, the impatient children moved on, and Jim Bates moved along with them.
A short time later, Ronald O'Bryan, who'd hung back at the darkened home, caught up with them. His hands were stuffed with five giant Pixy Stix — a colourful, powdered sweet that comes packaged in paper straws.
"You’ve got rich neighbours," he told Bates, giving one to each of the children. "Look what they're handing out."
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Back at home later that evening, Timothy asked to eat one final lolly from his haul before he went to bed. He chose the Pixy Stix.
The candy inside was clumpy, Timothy told his father, who then crushed it a little inside the straw. And it tasted bitter.
Within minutes of swallowing, Timothy was vomiting and convulsing. Ronald phoned an ambulance, but the boy died on route to the hospital.
A frantic search uncovered the four other Pixy Stix: neither Elizabeth O'Bryan nor the Bates children had opened theirs. Ronald had given the other to a trick-or-treater who came by their home later in the evening.
In each case, the straw appeared to have been tampered with and stapled closed.
"That's what saved another boy's life that night," a detective on the case later told Vice. "They found him in bed with the sweet in his hand, but he wasn't strong enough to undo the staples."
An autopsy on Timothy revealed he'd been poisoned with Potassium Cyanide, a chemical used in gold mining and jewellery making that looks similar to sugar and is lethal when ingested — even in small doses.
"He seemed too cool, calm and collected."
The man who lived at the darkened house was arrested and taken into custody after being identified by Ronald O'Bryan as the man who gave him the Pixy Stix.