Martha meets the Stranger and learns his true identity. Claudia tries to prevent Egon’s death in 1987. Hannah travels to 1954 to see Ulrich.
In 1954, a missing Helge returns, but he’ll only speak to Noah. In 1987, Claudia brings the time machine to Tannhaus, and Egon questions Ulrich again.
In 1953, the disfigured bodies of two boys are exhumed at a construction site, the future location of Winden’s nuclear power plant.
Peter gets a shock. Jonas learns the truth about his family, but there are more surprises still to come. Helge makes a sacrifice.
Ulrich runs afoul of the law, Helge tries to dodge Egon Tiedemann, Claudia harnesses the cave’s powers, and Katharina lashes out at Hannah.
Crucial evidence literally falls into Rath’s hands, while Lotte unearths a conspiracy to murder an international envoy.
Lotte is kidnapped and held in an ominously familiar location, while Rath and Benda’s case against the Black Reichswehr stalls.
Lotte’s private investigation leads her to the depot where the hijacked train is held. Rath relives painful memories of the front.
Kardakov flees after the Soviet attack on The Red Fortress. Rath receives an uninvited guest in his apartment.
A German biker gang embarks on a home-invasion spree. Meanwhile, Sebastian goes undercover for the first time.