S3·E11 Seasons of Belief

On Christmas Eve, a couple decide to preoccupy their restless children by telling them a fable concerning a massive, winged creature called "The Grither". The children initially balk at the story, which describes the creature as a proud, hateful beast who becomes enraged when it hears its name being spoken aloud. Although it lives at the North Pole, its humongous ears allow it to hear its name being spoken from anywhere in the world, and the parents assure the children that The Grither is well on its way to their house to kill them. The children become progressively more frightened as the story continues, eventually to the point of utter hysteria. Finally, in an effort to calm their children, the parents reveal that the story is make believe. At that moment, the huge arms of The Grither smash through the windows of the house and break the necks of the parents as the children look on in horror.