Tchaou is a young male puppy abandoned shortly after birth, discarded in a box set adrift on a city river. This traumatic separation from his mother fuels his persistent journey to reunite with her. He clings to the box as a symbolic connection, reflecting initial naivety.

Early experiences involve near-drowning and urban dangers, emphasizing vulnerability. Rescue comes from an older, experienced stray dog named Shanabo (also known as Nora or Big). This relationship forms the foundation for Tchaou's survival education. Shanabo teaches harsh street realities: scavenging for food, evading humans, and navigating treacherous rooftops and sewers. Lessons stress human hostility towards strays, fostering awareness of cruelty and exploitation.

Encounters with other dogs expose Tchaou to distinct philosophies on independence and coexistence with humans. These interactions shape his resilience, understanding of pack dynamics, and reinforce his quest for his mother. Core traits of innocence and determination endure despite hardships.

A mysterious breeder acts as an ongoing antagonist, observing Tchaou from afar. This breeder deliberately orchestrated the abandonment to force adaptation to street life, intending later recapture to train Tchaou as an elite fighting dog capable of defeating opponents like Alaskan polar bears. This threat adds external pressure.

In the non-canon theatrical film adaptation, Tchaou's core abandonment and stray experiences remain, but the driving motivation to find his mother is absent. Instead, the narrative focuses on episodic survival alongside mentor figures in labyrinthine sewers, featuring lighter moments like chasing butterflies, lacking the overarching familial search.