Serial killer Keith Hunter Jesperson left a trail of horror across the West Coast, including the grim discovery of a body near Salinas.

“Happy Face,” which begins airing Thursday, is inspired by the true story of Melissa Moore, whose father was a prolific serial killer infamous for drawing smiley faces on letters to the media and prosecutors. She was just 15 when he was captured.

In December 2024, the convicted killer called in to “The Lighter Side of True Crime With Keith Rovere” podcast to promote his book, “Happy Face: A Family of Monsters (Straight from a Serial Killer),” which hit shelves in January. A description for the book describes it as giving “unparalleled access to a serial killer’s mind.”