Fourteen year-old Rusty-James idolizes his elder brother, the Motorcycle Boy, and wants to be just like him. Once the leader of a huge street gang, Motorcycle Boy remains calm, even laughs, in the face of danger. He is the toughest street-fighter around and the most respected guy on their side of the river. Suddenly Rusty-James' brother changes, becomes a loner and shuns gangs and fighting, comparing them to rumblefish - Siamese fighting fish so ferocious that they attack their own reflections in a mirror. Rusty-James is torn between blind adoration for his brother and an eagerness to return to the days of street fights and both boys rush heedlessly into danger.