It was one of the most confounding unsolved crimes that the town of West Springfield, Massachusetts

had ever seen. Two young people shot and killed in their car without any conceivable motive.

This seemingly random double murder remained unsolved for over 40 years until police received a new

tip that finally unraveled the entire mystery and led them to the door of a suspected killer.

I'm Kylie Lowe and this is the case of Mark Harnish and Teresa Markoo on Dark Down East.

It was just after 9.30 a.m. on November 19, 1978, and patrolman Earl Camp was driving

down Route 5 in West Springfield, Massachusetts, when he passed the

rest stop between the Memorial and North End bridges. As he glanced over at the parking spots,

he noticed something concerning. According to reporting by Kelly Christman for the Morning Union,

parked there in the lot was a beat-up pickup truck. The officer had seen the

same truck earlier that morning and it hadn't moved, but seeing it again, he realized that a window

was shattered. Getting out of his cruiser and approaching the vehicle, the officer saw what

appeared to be blood pooling beneath the truck and a trail of it leading towards the edge of

the parking lot. At that moment, he dreaded what he might find inside the truck's passenger

compartment, but a tentative peek inside revealed it was empty, except for even more blood.

The officer followed the trail in the parking lot away from the truck for about 15 feet,

past a blood-smeared guardrail, and down over an embankment past a concrete retaining wall.

That's when he found them.

Two people, their lifeless bodies laying face down on the riverbank,

about five feet apart from one another.

It appeared they'd suffered multiple gunshot wounds to their heads.

Patrolman camp called for additional units to respond to the location, and soon the rest

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