Contains spoilers for this episode and earlier episodes.
On 27 June 2020, Winden reaches the day of the apocalypse. Adult Jonas forces Martha into the bunker at gunpoint, hoping to prevent the death he remembers, but she leaves when Peter and Elisabeth arrive. Young Noah gives adult Jonas a letter from Martha, and Jonas later gathers Magnus, Franziska and Bartosz around a time machine. The younger Jonas reopens the cave passage with Claudia before they return from 1987, who brings the cancer-stricken Regina to the bunker, where young Noah also takes shelter.
In 1921, Noah confronts Adam over the truth concealed in the notebook. Charlotte is Noah and Elisabeth's daughter, while Charlotte later becomes Elisabeth's mother. Noah tries to shoot Adam, but his gun fails to fire; Agnes takes it and kills her brother. In 2020, Clausen orders the buried barrels at the power plant opened despite Charlotte's warning. A rift connects her to adult Elisabeth in 2053, and mother and daughter reach toward each other as the catastrophe develops. Katharina enters the reopened passage as the disaster unfolds.
The younger Jonas reunites with Martha at his house, but Adam arrives and shoots her. Adam tells Jonas that this loss will help turn him into the man standing before him, then leaves. Jonas stays with Martha as she dies and the shockwave spreads across Winden. Another Martha suddenly appears beside him with a small spherical device. She says she is not the person he thinks she is and indicates that she comes from another world.