In 1976, accompanied by his parents in the behind-the-scenes of the S.P.A., Boule, a little red-haired boy, discovers an English cocker spaniel nobody wants and asks his parents to adopt him. His mother accepts, but his father refuses to take care of it. Boule names the dog Bill, after "Bill l'Éclair" (according to him). When Bill tries to escape during his first bath, the house is turned upside down. Later, when Boule returns home from school, he finds a tortoise named Caroline, whom Bill immediately falls in love with.