Bizarre occurrences give Charlotte a sense of déjà vu, and she suspects Peter is hiding something. Franziska snaps when Magnus confronts her.

Hannah takes her obsession with Ulrich too far. The stranger asks Regina to deliver an important package. Martha is torn between Jonas and Bartosz.

In 1953, the disfigured bodies of two boys are exhumed at a construction site, the future location of Winden's nuclear power plant.

Jonas meets an ominous figure. While the kids comb the cave for answers, the adults gather in the bunker to share what they know about the travelers.

Armed with a plan to prevent the apocalypse, Jonas travels to 2019. During the Nielsens' anniversary party, Ulrich sneaks off with Hannah.