Three siblings gather to celebrate the birthday of their father, on the island of Ré. This is Adele, the elder of the two sisters, who had the idea to organize this surprise. Alice and Antoine adhere immediately. Arnaud, the eldest, is sidelined because of his bad temper. But then they make their way to the family home, an incident occurs. A black cat crossing the road when the father arrived by motorcycle. It is the accident.