Halloween that magical time of year when we prepare children to dress up in costumes and knock on strangers doors to ask for treats. It's a unique tradition with no clear origin.

Many traditions surrounding Halloween can be traced back 2,000 years

to the Celtic Sowen Festival,

which marked the end of summer and beginning of winter.

The dead were said to return to earth on this sacred night.

People gathered to light bonfires and offer sacrifices to honor the dead.

Villagers used animal skins to disguise themselves in costumes meant to drive away unwelcome spirits.

Treats were involved.

Tables were covered with food meant to calm evil spirits. Centuries later the custom evolved

with villagers dressing as demons and ghosts performing for the spirits

in exchange for food.

An early form of trick-or-treating that was rejected during the Reformation.

But these growing traditions around Halloween continued and immigrants brought the

custom to America in the 19th century. Ever since Halloween has preyed on our fears, while simultaneously serving as a way to have fun, especially

for kids.

But Halloween 1974 marked a shift in how we celebrate the holiday in America.

That night, a Texas man carried out a plan to kill his own son with trick or treat candy,

a real life horror story that stirred fear in the hearts of parents for generations.

Welcome to Southern Mysteries exploring exploring the history and mysteries of the American South.

I'm your host, Shannon Ballard.

This is the story of Ronald Clark O'Brien, the man who stole Halloween.

Poisined Halloween candy kills boy. Poisoned Halloween

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