World's Most Evil Killers (2018)

S5E4 Keith Jesperson

The Happy Face Killer delves into the unsettling story of a serial murderer known for his eerie confessional letters, which he would conclude with cheerful smiley faces. These correspondences were directed at both the media and prosecutors, adding a disturbing layer to his already horrific crimes. The episode examines the mind of this killer and the impact of his taunting messages on those investigating the case.