A dead man is found at Hanover Airport. Inspector Torsten Falke and Inspector Julia Grosz from the Federal Police quickly realize that the man fell victim to a gang of smugglers operating at the airport. Apparently the dead man had dangerously got in the way of the gang during one of their actions. Another passenger has also disappeared. It turns out that an IS returnee apparently managed to slip through a security hole in the airport and get into the city unnoticed. Is he planning an assassination? The two federal police officers have little time to prevent a possible catastrophe.