Worth Watching: ..., an 'Evil' Halloween to Remember, ...Evil (10/9c, CBS): "Do you want to do something really scary?" Let me rephrase that: Do you want to see something really scary? The quote, spoken by a mysterious little girl in a Halloween mask, is an invitation to watch one of the creepiest hours of TV so far this fall season‑and unquestionably the scariest episode to date of this macabre exploration of faith-vs-science, which was just renewed for a second season. (The first season of 13 episodes will wrap Jan. 30.) The centerpiece is a grueling Halloween-night exorcism, fueling a debate between wannabe priest David (Mike Colter) and psychology-oriented Kristen (Katja Herbers) about whether the victim is actually possessed or if the exorcism may be exacerbating an already disturbed mental state. (Either way, the scenes are terrifying.) On a lighter and more satirical note, professional debunker Ben (Aasif Mandvi) tags along with a Ghost Hunters-like TV team to poke holes in their latest investigation — of a haunted strip club. But the most lingering chills involve Kristen's four daughters, who spend their Halloween playing spooky games that become all too surreal. Why, you may wonder, does Kristen keep leaving her kids with their irresponsible grandma, Sheryl (a very amusing Christine Lahti)? But even Sheryl is about to have her own encounter with evil, the sort of moment that leaves you impatient for the next episode.