On a more somber than usual outing of CBS' hit The Mentalist (10/9c), directed by Simon Baker, the trail of a serial killer leads Patrick Jane to a blogger (the excellent David Paymer) who's as obsessed by this case as Jane has long been with Red John. "This [San Joaquin Killer] is a man to be feared, not pitied," the blogger insists to Jane, whose views on who-dun-it differ significantly, and the trap he prepares to prove his theory has unintended consequences.