A brilliant toy company roboticist uses artificial intelligence to develop M3GAN, a life-like doll programmed to emotionally bond with her newly orphaned niece. But when the doll's programming works too well, she becomes overprotective of her new friend with terrifying results.
When his dysfunctional family clashes over the holidays, young Max is disillusioned and turns his back on Christmas. Little does he know, this lack of festive spirit has unleashed the wrath of Krampus: a demonic force of ancient evil intent on punishing non-believers.
