East Germany in the early 1960s. Lotte Reinhardt, a 26-year-old shipyard worker, has a dream: she wants to become an astronaut. She shares her passion for space travel with her grandfather, a rocket engineer who, after fleeing the Soviet Union, develops new rocket propulsion systems in Augsburg. He and his granddaughter soon come under the Stasi’s scrutiny. After the Berlin Wall is built, Lotte joins a resistance group in the GDR. However, her boyfriend Holger informs on the group to the Stasi. Shortly thereafter, he is dead. The murder is pinned on Lotte. Her only option is to flee to the West. In Augsburg, she falls in love with Oskar, a scientist on her grandfather’s team. But Stasi officer Moll tracks Lotte down in the West and offers her a treacherous deal.