When teenager Theresa Bier mysteriously vanished in California's Sierra National Forest in 1987, a surprising suspect emerged: Bigfoot. Now, investigator Jessica Chobot and 29-year LAPD veteran Robert Collier reopen one of the most bizarre missing persons cases in modern history in hopes of bringing closure to Theresa's unsolved disappearance.

Stranger than the lore that surrounds it, this mind-bending mystery compels the pair to reinvestigate the decades-old disappearance in search of new clues and evidence that may finally solve this unusual cold case once and for all. Interviewing witnesses who have never spoken publicly, exploring new photos, retracing Theresa's final moments, and digging into recently uncovered police reports about possible drug trafficking, serial killers and unspoken family drama, the duo unravels new theories about what may have happened on that fateful day. And why, amid all the evidence, people in her hometown accepted that Bigfoot was not just lore…but her murderer.