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.
Ulrich runs afoul of the law, Helge tries to dodge Egon Tiedemann, Claudia harnesses the cave's powers, and Katharina lashes out at Hannah.
Ulrich questions a frail and frightened Helge in the nursing home. Jonas searches for Mikkel, but the stranger warns him about meddling with the past.
Adam holds Martha captive in 2020. On the day of the apocalypse, an increasingly frantic Martha begs Bartosz for his help.
Martha travels to 1888 to warn her friends about the 2020 disaster. Winden residents past and present search for their missing loved ones.
It's 1986, and Ulrich's brother, Mads, has been missing for a month. Confusion reigns as past and present intertwine.