David Rée's ancestors have been responsible for the accidental deaths of various French intellectuals on the roads in and around Paris. To escape this 'family curse' David’s father left Paris in the mid-1960s, along with his wife and son. David is now a leading genome scientist and knows that talk of curses is nonsense. When he is invited to Paris to attend a major conference, his ailing father (whom we never see) decides to accompany him. Once in Paris, David discovers that his father has gone missing without leaving a message. Aided by his father’s notebook, a photograph and a sequence of Frenchmen, David unravels a series of clues that lead him to a riverbank restaurant outside Paris. David makes a lifechanging discovery, which is followed by a further revelation in the show’s moving final scene.
Meanwhile, the ghosts of three French intellectuals — all killed in road accidents involving David’s ancestors — intersect the action. Roland Barthes muses on maps, writing and pleasure. Ernest Chausson takes a cycle in the woods, where he confronts his composer's block. Pierre Curie tells of his relationship with his wife Marie and their discovery of the properties of radium. During the show each of the historical characters describes his death. Their presence helps Here's What I Did to accumulate its themes of creativity and chance, fancy and fate.