After leaving school, young Lilly Borchert (Maria Dragus) wants to study medicine and see the world. She is accepted into the navy and fights her way through the first few weeks of basic training. Despite some reservations about Lilly’s suitability, she is accepted as a cadet on board a large sail training ship. The regular crew under Captain Krug (Harald Schrott) and the young cadets, who are aiming for a career as an officer, form a close-knit community. The masculinity, the lack of sleep, the drill – all this is alien to Lilly. Klara (Lisa Hrdina), also a medical officer candidate, becomes Lilly’s adversary among the cadets. Lilly defends herself against attacks from all sides, bites through, writes to get her frustrations off her chest and counts the days until her birthday, when she is allowed to visit her parents. But she suffers from severe abdominal pain and sleep problems. The instructors’ assessments of Lilly don’t get any better: “There’s no sign of her suitability as an officer” – “She keeps falling asleep” – “No team spirit – no leadership personality”.

One night – a good 24 hours before her 19th birthday – Lilly takes over the duty of a comrade at the lookout post. Suddenly, some cadets think they hear a scream. It is 11.43 pm, the night is pitch black and the water is 15 degrees. The crew shout their orders against the wind: Man overboard! Lilly is no longer in her position. Initial rescue efforts are unsuccessful and the search remains fruitless. Questions arise: How could Lilly have crashed? The journalist Hartmut Kerber (Miroslaw Baka), who is present on the ship, begins to investigate. Will he find out what happened that night?