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.

Ulrich looks to the past for answers and dredges up disturbing family secrets. Armed with new tools, Jonas probes the cave’s murky depths.

It’s 1986, and Ulrich’s brother, Mads, has been missing for a month. Confusion reigns as past and present intertwine.