High school students Lukas, Agathe, and Tom leave Paris for Berlin. It's their last trip before they graduate from high school. Lukas' father, who was German, said that in 1984 he crossed the infamous wall that divided the city in two in 1961. But on the memorial honoring those who died trying to cross over from East to West, Lukas finds his father's name. How can this be? A pulse-pounding investigation begins in the Berlin of 2019, where past, present, and future intertwine.