When ten-year-old Lukas disappears from his Copenhagen school, police investigators discover that the boy had a peculiar obsession with pareidolia: a phenomenon that makes him see faces in random things. A photo on his phone, posted just hours before his disappearance, shows an old barn door that resembles a face. Journalist Heloise Kaldan thinks she recognizes the barn—but from where? When Lukas's blood-flecked jacket is found in the moat at Copenhagen's Citadel, DNA evidence points to Thomas Strand, a former soldier suffering from severe PTSD. But then Strand turns up dead in his apartment, shot in the head execution style. What did the last person to see Lukas really witness that morning in the school yard? Was it really Lukas, or was it an optical illusion? Can you ever truly trust your eyes?