In the meantime, Sam meets brothers Edgar and Alan Frog, self-proclaimed vampire hunters who give Sam horror comics to teach him about vampires. Sam scoffs at them until Michael's developing vampirism becomes clear; their dog Nanook is forced to fend off Michael's bloodlust-driven attack on Sam, who notices that Michael's reflection has become transparent.
Sam turns to the Frog brothers for help, but refuses their advice to kill Michael. He turns their suspicions to Max, who has begun dating Lucy, suggesting that he is the head vampire whose death will free half-vampires such as Michael, who have not yet killed anyone. At a dinner party help by Lucy, they put Max through a series of tests (including the use of garlic and holy water), which appear to indicate that he is normal, and also embarrass Lucy greatly.
Michael resists joining the gang when they enter a feeding frenzy. Star reveals to Michael that she too is a half-vampire, and wants his help. The next day Michael leads Sam and the Frog brothers to the gang's lair, where they intend to kill the vampires in their sleep. But the killing of one vampire awakens David and the two others, and the Emerson brothers, Frog brothers, Star, and Laddie, a recently abducted child half-vampire, barely escape with their lives.
That evening, while Lucy is on a date with Max and her father is out of the house, the teens arm themselves with weapons based on traditional defences against vampires. David and the others attack, and are each killed spectacularly, with Michael ultimately impaling David on a pair of mounted deer antlers. However Michael doesn't transform back to normal with David's death, as they expected.
Max and Lucy arrive, and Max is revealed as the head vampire, having passed the Frog brothers' tests only on the technicality of having been invited into the house. Max's objective all along was to get Lucy to be a "mother" for his "lost boys", but his grand plan is ruined by Grandpa, who has been aware of the vampires all along, crashing his jeep through the wall of the house, impaling Max on the wooden fence posts he was carrying. Michael, Star and Laddie return to normal. The film ends with Grandpa calmly retrieving a drink from the fridge, seemingly oblivious to the carnage around him. He then declares, "One thing about living in Santa Carla I never could stomach...all the damn vampires".