“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.

Melissa Moore grew up with a father who turned out to be the Happy Face Killer. How true is Dennis Quaid's portrayal in the 'Happy Face' crime series?

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.”