Rüdiger, a bored young vampire, is sent into town and ends up following 10-year-old Anton home. Later that night he shows up at Anton’s window, forcing Anton to keep his nerves (and his room) under control while a babysitter prowls the house. Their strange first meeting turns into an unlikely friendship just as a new handyman arrives at the cemetery with a very specific interest in vampires.
Anton invites Rüdiger over for another secret visit, but plans change when Anton’s mother is stuck at home with an injured ankle. Rüdiger introduces Anton to flying powder and the basics of midnight “cloak travel,” until the practice gets a little too noisy. Anton’s quick cover story helps, but the vampire cloak ends up in adult hands, while the new cemetery gravedigger settles in and starts being watched from the shadows.
Uncle Theodor is convinced the new gravedigger is a Geiermeier, and the vampires start taking precautions. Anton’s usual babysitter is replaced by Effie, and Rüdiger’s attempt to scare her goes a bit too well, pushing the boys into a late-night dash to the cemetery. Anton gets his first visit to Rüdiger’s crypt, where hiding as a human becomes a real challenge.
Anton’s mother washes the vampire cloak, then cheerfully tells Anton to return it and invite Rüdiger and Anna for dinner. At the cemetery, Anton tries to fly but cannot, and classmate Udo/Cyril notices everything. The gravedigger recognizes the cloak for what it is, and before Anton can fix the mess, the cloak ends up somewhere even harder to retrieve.
Geiermeier documents his vampire-hunting “career,” while Rüdiger brings Anna to help recover the missing cloak. Anton distracts Udo/Cyril so Anna can sneak in and grab it, but flying powder in the wrong place causes chaos at home. Back at the crypt, Anton has to stay hidden again when powerful family members appear, and the night takes an unexpectedly dramatic turn.
With dinner at Anton’s house approaching, Rüdiger and Anna need convincing human disguises fast. Rüdiger borrows Anton’s old clothes, while Anna sets her sights on a dress she saw at Udo/Cyril’s place. Meanwhile, Geiermeier hunts down information about vampires in the most blunt way possible, and the vampires realize someone might be listening closer than they think.
Anton’s parents brace for a very unusual “tea visit,” and Rüdiger and Anna finally arrive in human clothes and makeup. The vampires’ table manners are a performance, watched closely by suspicious relatives hiding nearby, and even small details become a big deal. When the evening ends, getting safely back to the cemetery turns into a problem the kids did not plan for.
After the dinner disaster, Rüdiger is forced to spend the night outside the crypt and arranges a risky hiding place near Anton’s world. He needs his cloak to leave town safely, but it goes missing at the worst possible moment. Anton races to track it down and learns that “helpful” adults can accidentally cause supernatural-scale trouble.
Rüdiger hides in Anton’s cellar while Anna visits and reports growing doubt inside the vampire family. Plans for the upcoming Big Vampire Party stir up rivalry and mixed feelings, and Geiermeier makes an alarming public promise at the cemetery before landing in trouble with the police. Anton also stumbles onto a reminder of his old friend Teddy, pulling another thread into the story.
Anton hears troubling news about the cemetery and wants the vampires to act, but Rüdiger is focused on the Big Vampire Party where “everything is forgiven.” Anton dresses up and joins him, only for Udo/Cyril to show up in costume too, eager to learn the secrets of flying. The night leads them from the cemetery to a hidden party place where Anton must improvise a new identity to fit in.
The party continues with one bizarre dance after another, but Anton’s disguise starts to fail, and leaving early is not as simple as it should be. In the tunnels outside, they run into a “vampire” who is far more dangerous than a costume, and the group has to make quick decisions just to get back above ground.
With demolition work starting, Anton realizes the vampires are in immediate danger and takes a daytime risk to reach the crypt himself. He finally admits who he really is and tries to convince the family to listen before it is too late. Theodor gives Anton a practical mission that forces him into the grown-up world of negotiations, timing, and an escape plan that has to work in one night.
The Schlottersteins prepare to leave, but moving a vampire household is harder than it sounds, especially with coffins involved. Halloween creates the perfect cover for a strange “procession” through town, but Geiermeier pushes the police to intervene, and Anton is pulled into the middle of it all. As the night builds toward a goodbye, Anton is left with a reminder that some friendships do not end just because the road changes.