In late summer of 1990, a mother in Central Maine seemed to slip quietly out of her own life.

Shirley McAvoy had been navigating a painful separation, and she was leaning on friends and trying to rebuild a sense of normalcy.

Then, shortly before a scheduled court date related to her pending divorce,

she simply disappeared, days turned into weeks, and small unsettling details began to surface,

details that didn't fit with the idea of someone who'd chosen to leave. What started as a missing

person's case

slowly transformed into something far more disturbing,

stretching well beyond the quiet town

where Shirley was last seen.

More than 35 years later,

investigators are still trying to identify

a mystery man believed to know exactly what happened to Shirley.

I'm Kylie Lowe and this is the case of Shirley McAvoy on Darkdowne East.

32-year-old Shirley McAvoy was trying to find a new path forward in life.

Everything she knew for the last 13-plus years was falling apart.

She and her husband, Brian McAvoy, were already separated, and next would be divorce papers.

According to reporting by Brenda Seekins for the Bangor Daily News,

Shirley was living alone with her two dogs in Pittsfield, Maine, while her two young daughters were in the custody of their father.

It wasn't an easy adjustment, and friends said that she dealt with bouts of depression for everything she'd been going through. To fill the quiet and loneliness of that summer in 1990,

Shirley did a little redecorating at her home on Berry Road, putting up curtains for some extra

privacy in the dining room, and adding a matching bedspread to bring the look together.

She also spent some time with friends and made new ones. In fact, on the night of August 8, 1990,

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