Colombine finally wants to know who her father is. But her mother vehemently refuses to tell her. With the help of Mathilde the greengrocer, Colombine obtains a magic potion that transports the 13-year-old several months back in time to the « Fête des Vignerons » wine festival in Vevey. There, Colombine must summon up all her courage to uncover the secret of her father.