Remi Barberin, a foundling raised in Chavanon, France, by his foster mother, believes he is her natural son. His life fractures when his foster father, Jerome Barberin, reveals his adoption and sells him to the traveling performer Vitalis due to poverty. This act propels Remi away from home.

Journeying across France with Vitalis and his animal troupe, Remi learns music and performance. Vitalis becomes his mentor and father figure, teaching him reading, survival, and resilience. During their travels, Remi experiences both kindness and cruelty, including a period of refuge with the affluent Milligan family—Mrs. Milligan and her son Arthur—unaware they are his biological mother and brother. He chooses to leave them and continue traveling with Vitalis.

Tragedy shapes Remi when Vitalis and the animals perish in harsh conditions, leaving Remi alone except for the dog Capi. He finds temporary stability with the Acquin family, forming a close bond with Lise, their mute daughter. They are separated when Remi is wrongly imprisoned, forcing him back into a nomadic life. He later reunites with his friend, the gifted violinist Mattia, and together they perform music to fund Remi's search for his origins.

This quest takes Remi to London, where he stays with the Driscoll family—criminals who falsely claim him as their missing son. After the Driscolls are arrested, Remi is briefly implicated but escapes with Mattia's help. Returning to France, he unravels his true identity as Richard Milligan and reunites with his birth family. His relationships resolve: Lise regains her speech, Arthur recovers his mobility, and Mattia is adopted by the Milligans. A decade later, Remi becomes a lawyer and marries Lise.