Teen girl vanished exploring woods with older man who insisted ‘Bigfoot took her’

Theresa Ann Bier left home in Fresno, California, with 43-year-old Russell Welch, to search the Sierra Nevada wilderness for traces of Bigfoot in 1987

On an early summer’s day in 1987, Theresa Ann Bier skipped school to explore the Californian wilderness with an older man instead. Tragically, she never returned home.

It’s since been called “one of the most bizarre missing persons cases in modern history”. Why? Because one of two the main suspects, is none other than Bigfoot.

And it’s now been reinvestigated again almost 40 years after Theresa disappeared without a trace.

Theresa, then 16, left home in Fresno, California, on June 1, 1987, with 43-year-old Russell Welch, who was known to pals as Skip. Their plan was apparently to go camping in the Sierra Nevada on a trip to find Bigfoot.

When she failed to return, Welch was the obvious prime suspect. But things took an odd turn when he insisted to detectives that the mythical beast they had been looking for had in fact snatched Theresa.

He said the girl had chased after the hairy creature after they spotted it in Ghost Canyon, but when he turned around then back again, there was no sign of either her or Bigfoot.

A huge manhunt was launched as a search party, including people and dogs, looked in forests, meadows, ravines and along ridgelines. They found the girl’s belongings, including a purse, clothing, photos and personal items at a campsite, but nothing more.

No trace of Theresa or any meaningful forensic evidence ever turned up. Dogs picked up scent trails, but they didn’t lead anywhere.

Welch was charged with child-endangerment and child-stealing. However, prosecutors dropped the charges just three days before the trial in September 1987, citing a lack of evidence and the inability to guarantee a conviction without Theresa’s remains.

Detectives said Welch sincerely believed in Bigfoot creatures and claimed to have had continued contact with a tribe of them.

In the years since then, no credible alternative theory has emerged that explains Theresa’s disappearance. In 1998, Welch died from severe coronary artery disease at the age of 54. If he was holding onto any secrets about Theresa, he took them to the grave.

The mystery recently returned to public attention thanks to the new documentary series, Bigfoot Took Her. The series follows investigators as they retrace Theresa’s final days, interview previously silent witnesses and examine old police records.

The Discovery documentary raises unsettling questions about what might really have happened that night in the forest — whether Theresa truly vanished into the unknown or whether she was the victim of a crime that was never solved.

The synopsis states: “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.

“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.”