One spring evening in 1987, a college student got into a green car in Plymouth, New Hampshire, and vanished.

His friends believed he was coming back. His family knew he would have called if he'd left on his own, but he was gone.

And the man believed to be with him on the night he disappeared had a long history of run-ins with the law.

What started as a missing person's investigation soon stretched across state lines,

into jail breaks, forged identities, strange searches in the Vermont woods,

and disturbing yet inconclusive physical evidence.

Police identified one suspect at the time.

The missing man's family believes they know what happened.

But nearly four decades later, no one has ever been charged.

I'm Kylie Lowe and this is the case of Patrick Merrill on Dark Down East.

It was April 6, 1987, and 21-year-old Patrick Merrill had quite a few plans for his Monday night.

He and his friend Nancy were supposed to meet up around 8 p.m. to hang out, but before that,

Patrick had to take care of some pre-arranged business.

A few of his close friends knew exactly what kind of business Patrick was up to.

In fact, some had a stake in the transaction.

And I can imagine they were waiting for him to come back that night,

maybe watching the clock,

maybe feeling a little anxious for him to return.

Of course, Nancy was waiting too.

According to reporting by Paul R. Lassard for the New Hampshire Union leader, 8 p.m. came and went.

Then more time passed. And at some point, what might have started as an annoyance or confusion turned into something sharper.

Patrick wasn't just late. No one knew where he was. Nancy started checking in with Patrick's other friends,

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