Léna, a 28-year-old community manager, has just joined the Paris Police Headquarter's communications department that is seeking to update its image. At the same time, a serial killer is on the loose in the capital.

Michele, is homeless and lives at Orly airport. Theo, a mentally handicapped man, works at airport and lives with his Auntie who has been overprotecting. Michele decides to find her son in Lisbon, Theo naively agrees to drive her.