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On a hot and humid Tuesday, 24-year-old Mandy Alexander went into work a closing shift.

She had just been hired on at a discount bakery store in downtown Great Bend, Kansas.

And she was excited to make the best of it.

Unfortunately, just three days into her new job, Mandy would find herself the victim of a brutal and violent murder.

79-year-old Mary Drake had been a lifelong resident of Great Bend.

On the evening of September 4, 2002, she decided to stop in at the local discount bakery to pick up a loaf of bread.

She would never make it home, having apparently stumbled upon Mandy and her killer either moments before or perhaps during the horrendous assault.

Moments later, an unidentified man stepped out from the bakery, stuck the keys into the lock and secured the door behind him.

Passing a potential customer in the process, the man quickly noted that the bakery was closed.

More than 20 years later, he has never been identified, the keys have never been found, and the murder weapon remains unknown.

This is Trace Evidence, Episode 228, the murders of Mandy Alexander and Mary Drake.

Welcome to Trace Evidence. I'm your host, Stephen Pacheco.

Today we examine a case that is truly as frustrating as it is heartbreaking.

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