Intriguing new developments in a story that has mystified Chicago for 40 years.

Investigators are ramping up their efforts to solve.

One of the most notorious unsolved cases in the U.S.

In September 2022, right before we were about to publish our first story on the Tylenol murders, we got a call.

There was a new development in the Tylenol case.

In Chicago Tribune reporters, Christi Gertowski. St. Clair is one of the Tribune's reporters.

Investigators flew to Massachusetts to interview their main suspect.

A bit of an enigma. He's really the only known, living person of interest.

James Lewis. Law enforcement has told the prosecutors they have a chargeable, circumstantial

case.

Authorities last spoke to James Lewis about a decade ago, after they raided his home.

Back then, they collected papers and other items from his cluttered condo.

Now, investigators offered to return one of his personal items if Lewis would talk to them.

He agreed. Multiple sources told us that Lewis talked without a lawyer present for hours on tape at a holiday inn. For so long,

investigators have centered their attention on Lewis.

Why were they still so certain it was him?

After months of reporting, we learned their best evidence was collected in one place,

a PowerPoint presentation, one that investigators hope will sway prosecutors to charge the case before it's too late.

And now renewed hope for the families of the seven victims that justice will be served.

I'm Christy Katowski.

And I'm St. Clair.

This is Unsealed.

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