Katharina Nielsen

Katharina Nielsen runs the local school with the same brisk authority she brings to her own household, married to Ulrich and raising three children in the small town of Winden. When her son Mikkel vanishes, she becomes the town's most visible parent in crisis — controlled, exacting, and unwilling to accept comforting explanations.

Jördis Triebel plays her as armor rather than ice: the control freak instinct reads as love that has nowhere else to go once the ordinary rules of cause and effect stop applying. As Dark's mysteries multiply, she stays the character least willing to be lied to, which makes her scenes a kind of pressure test for everyone else's secrets.