During one of her risky forays, Helvi meets Heinzels she doesn't know, who are much cooler than her normal family and also share Helvi's thirst for adventure. A series of fun endeavours by the little Heinzel girl and her new friends are disrupted by the human and overambitious inspector Lanski. Together with her super-sniffer cat Polipette, the policewoman wants to prove the existence of the Heinzels at all costs. For Helvi, this means she has to come up with a plan to protect her Heinzel family and her new friends.