Martha Nielsen

Martha Nielsen is a Winden schoolgirl navigating an awkward split with her boyfriend Jonas just as her town's children begin disappearing. Quick-witted and a little guarded, she's caught between old feelings for Jonas and a new relationship with Bartosz, trying to hold her family and friendships steady while everything around her starts to unravel.

Dark surrounds Martha with cosmic paradox and generational tragedy, but keeps her grounded as an ordinary teenager with real, messy feelings—which makes her a steady emotional anchor amid the show's dizzying structure. Lisa Vicari plays her with an unforced naturalism, so that even as the mysteries multiply, her confusion and stubbornness feel utterly human.