While Max, Lucie, and Jean-Guy organize a search party to find Gwen, Wendie flatly rejects what's happening to her. But when Léa and Nathan tell her they've found a way to communicate with her grandmother, the teenager finally resigns herself to helping them.

Wendie, Léa, and Nathan research the founding families of Harz and learn more about the folklore and mythology that inspired the culprit. Max and Lucie set up a stakeout to keep a close eye on their only suspect.