Lena Ferben (Maria Schrader), a successful academic, suddenly suffers severe retrograde amnesia caused by an undiagnosed case of encephalitis. While she retains her basic vocabulary and cognitive function, her entire biographical memory and emotional connection to her past are erased. Her husband, Tore (Johannes Krisch), attempts to help her reconstruct her identity and remember their shared life. Disconnected from her former self's social constraints, Lena experiments with her personality, reads her old diaries aloud to friends without filter, and engages in impulsive sexual encounters—uninhibitedly building a completely new identity that increasingly alienates Tore.