During a canoe trip, neurologist Magnus Heier suffers from sudden amnesia: for eight hours, he records nothing. Everything he does is immediately forgotten. This episode becomes the starting point for an exploration of his own memory. How can his functioning explain the incident he suffered? And what happened to the doctor during those lost hours? To understand the amnesia that has affected him, Magnus Heier embarks on an investigation among his peers. His journey takes him to Finland, Germany and Italy, where he visits researchers working on the astonishing brain faculty of memory.