It was a crisp Thursday evening on October 31, 1974, Halloween night, when eight-year-old

Timothy O'Brien returned home to Deer Park, Texas, clutching a pillowcase brimming with candy.

The full moon hung low over the suburban streets, casting long shadows of cross-carved pumpkins

and leaf-strowned sidewalks.

Kids and costumes still darted between porch lights, chasing the final thrills of the night.

Timothy had been trick-or-treating with his five-year-old sister, Elizabeth, their father Ronald at their side, along with the neighbor and his children.

And it had been a night like so many others,

laughter, sugar highs,

and the comforting rituals of Halloween in small-town America.

When they returned home,

Ronald allowed Timothy and Elizabeth

to choose one piece of candy each before bed,

a small sweet reward to end the perfect evening.

Timothy chose a pixie-sticks.

Moments later, he was gasping for breath,

vomiting and convulsing.

By the time the ambulance arrived, it was already too late.

Timothy's sudden and shocking death sent waves of panic through the community.

Could a stranger have slipped poison into a child's Halloween candy?

Was this the nightmare parents had long feared? The urban legend made real?

But as investigators dug deeper, they uncovered something far more chilling.

The truth about what happened that Halloween night

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