The teenagers are back in the 19th century in a machine factory with the Martha from the parallel universe. Claudia Tiedemann is one of my favorite characters and she's one of the very few survivors. Charlotte found Ulrich in the psychiatric facility. Tronte suffocated the older Claudia who's fighting cancer so that he could save her (!) The mute girl and her father are the other survivors and her mother is with her in the future. The old Martha said there'll be an apocalypse in her world in three days.