Previously on Unsolved.

Michael Uphorsky was a substitute teacher and part-time hall monitor at Franklin High School back in 1976.

As a juvenile and up until his teens and very early 20s, Mike Yuporski had been arrested a few times and had some contact with the

police due to actions that he would take with boys. When he was a kid, the boys were a little

bit younger than him, but then as he got into his late teens, they were about the same age.

And his history includes finding these boys and accosting them, taking off their shoes and socks, and playing with their feet.

Back in the 60s, when Mike Yuporski had these interactions with the police,

the police were very focused on trying to help him

because he didn't beat up the boys, didn't molest the boys,

and there was no indication that any of this was done for sexual gratification.

So although it was strange and it was disorderly conduct, it wasn't a serious crime.

You may recall that when John's body was found, he was unclothed, but also his shoes and socks were taken off, and the socks were tucked inside of the shoes,

which is something that the police thought someone with an unusual interest in kids' feet might do.

In interviews with other victims that, of course, he had, he would take the shoes, he would take the socks,

he would put the socks inside the shoes, he would lay him in a specific place.

The police were not able to find any evidence against Tuporski.

I did not either accidentally or on purpose take the life of John there.

If it proves that he is not our guy, yeah, I personally would feel bad that we've basically

kind of ruined this guy's life. From the Milwaukee Journal Sentinel,

this is unsolved, a murdered teen, a 40-year mystery.

I'm Gina Barton.

At the time of 14-year-old John Zara's death in 1976,

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