It's just before 5 a.m. on a Sunday. The location is a swingin casino in South Lake Tahoe.

The shows have all ended and the crowds have died down to almost nothing. Beyond the chintzy,

velveteen glamour and hurly burl of the floor shows, craps tables, the pits.

There sprawls a vast network of kitchens,

offices, storage, and custodial areas

connected by bland, non-descript hallways and passages.

Per state law, one such room on the dull end of the operation

is a nurse's station.

It's into this plurresent lit room that a nurse enters to begin her shift.

What strikes her is not the presence of anything out of the ordinary, but rather it's absence.

She is there to relieve her counterpart from the night shift.

Said counterpart is not in the office, however.

A quick look into the logbook reveals something strange.

At about 150 a.m., the other nurse had been writing a report about a gambler who had suffered a minor heart attack earlier that evening.

There's nothing out of the ordinary about that.

But the report ended abruptly, the

Penn's mark running down and then off the page mid-word.

That nurse's name?

Donna Lass, and she has been missing since 1970.

And the case that surrounds her is as baffling as any, pulling into its orbit two of the most notorious

criminals of the past two centuries and exactly zero concrete answers.

Featuring Joe Swaney from Thinking Side Race Podcast and filmmaker Vincent Calderney.

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