Adopted by his grandmother, Madame Souza, Champion is a lonely little boy. Noticing that the lad is never happier than on a bicycle, Madame Souza puts him through a rigorous training process. Years go by and Champion becomes worthy of his name. Now he is ready to enter the world-famous cycling race the Tour de France. However during this cycling contest, two mysterious men in black kidnap Champion. Madame Souza and her faithful dog Bruno set out to rescue him. Their quest takes them across the ocean to a giant megalopolis called Belleville where they encounter the renowned "Triplets of Belleville," three eccentric female music-hall stars from the '30s who decide to take Madame Souza and Bruno under their wing. Thanks to Bruno's brilliant sense of smell, the brave duo are soon on to Champion's trail. But will they succeed in beating the devilish plans of the evil French mafia?