In December 1978, best friends Kerry Graham (15) and Francine Trimble (14) vanished from Forestville, California. The girls were last seen heading to the Coddingtown Mall to shop for Christmas—but they never came home.

Seven months later, skeletal remains were discovered off Highway 20 in Mendocino County. Bound with duct tape and buried in a shallow grave, the victims were never identified. For nearly 40 years, they were known only as the Mendocino County Does.

In 2016, DNA testing finally gave the girls their names back: Kerry and Francine. But the answers ended there. Their killer has never been found.

This week on Find My Killer, we dive into the decades-long mystery of two inseparable friends whose story was nearly erased by time—and the chilling question that still lingers: who murdered Kerry Graham and Francine Trimble?

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