The Thirteenth Hour is the hour after midnight on All Hallows Eve when Satan and his minions are most powerful-and dangerous

In part one, thirteen teenage vampires kidnap a thirteen-year-old-girl, Emily, and are planning to sacrifice her to Satan during The Thirteenth Hour. A successful sacrifice would increase their powers thirteen-fold. Emily's friend, Amanda, finds out their gruesome plan, but she knows she can't fight the vampires alone. With the help of Hurts, a worn-out, old, private detective, they must find Emily before The Thirteenth Hour. Will they find her? Can they save her?

In part two, three days until Halloween. At the stroke of the thirteenth hour, Satan plans to impregnate a girl who turns thirteen on the day of Halloween to start Armageddon. There are three girls who were born that day, but nobody knows who the Chosen One is. The senior elder of a secret organization, The Community, begs private detective Hurts to help him stop Satan. Hurts confide in Amanda, Tom, and Tom's mother, Lill, and asks them to help him. They must find out which of the three girls is the Chosen One. They must prevent Satan from kidnapping her. They must stop the Armageddon. Can they do it all?