The official trailer for XX begins on a subway train. A young boy asks the man sitting next to him if he can see what's in the box the man is holding. Once the stranger opens it, the boy’s face is masked with horror. Next, a group of young adults are outside at a campsite. Little do they know, something is watching them from the forest. In the next scene, a woman is being told that her son tore off his classmate's finger nails.
We cut back to the first little boy, who is still traumatized by the box, and refuses to eat. He is told by a doctor that he must eat or he’ll die. He nonchalantly asks, “So?” As the music escalates, we get the titles of each film in the horror anthology, accompanied with flashes of some equally terrifying imagery.