Based on a book by Vicki Baum, all of the action takes place in one day in a luxury hotel in Berlin. Grusinkaya is a ballerina staying at the hotel, other guests include Baron von Gaigern a sophisticated thief, Otto Klingelein a dying man, Preysing a businessman, and a stenographer. Events intertwine the lives of these strangers, bringing them together for some dramatic moments.

When the Dutch resistance brings in Carla Van Oven to spy on the Nazis, Col. Pieter Deventer initially suspects she could be a double agent. Van Oven eventually convinces Deventer of her character, and when she is sent into occupied territory, she joins up with a rebel leader known as "The Scarf". As the resistance endures severe losses and their missions fail, Deventer starts to wonder whose side Van Oven is fighting on.