You're in the Midwest of Scare today for users of the nation's most popular over-the-counter pain killer, Tylenol.

It began when people in suburban Chicago died after taking the medication.

Authorities discovered bottles of the drug laced with cyanide.

If you look at a bottle of Tylenol today, it comes in a small cardboard box that's glued

shut. You open the box and there's a bottle inside. The cap is wrapped in plastic. When you

remove the plastic and unscrew the cap, there's a piece of foil attached to the top of the bottle.

Peel it back and there's the medicine. The glue, the plastic wrap, the foil, these are the three tamper-resistant seals used to convince

consumers that it's safe to take Tylenol.

Back in 1982, Tylenol bottles came in a similar paper box.

Except it wasn't glued shut. And when you opened the cap, which wasn't wrapped in plastic, there was no tamper-resistant foil.

There was only that little bit of cotton, which made consumers feel safe enough. If someone wanted to go into a store, open that little box, and say, put some poison pills into a bottle with the regular ones,

it would be pretty easy to do without anyone knowing and without leaving a trace.

I'm Christi Kutowski.

And I'm St. Clair.

This is Unsealed, the Tylenol murders.

Episode 2, Turf War.

The next day, after the Janus and went to the hospital, the lab results confirmed that cyanide was in one

of the most popular products in America, and the nation was in a full-blown panic.

The county medical examiners urged that all stores in the area withdraw the product until

investigators had determined whether the problem was at all widespread.

No one knew how many more poison bottles were out there, or where the killer might strike next.

We don't know the extent of the contamination, so I think at this time it would be wise not to take extra strength Tylenol at all.

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