Raised as a slave, Danny is used to fighting for his survival. In fact, his "master," Bart, thinks of him as a pet and goes as far as leashing him with a collar so they can make money in fight clubs, where Danny is the main contender. When Bart's crew is in a car accident, Danny escapes and meets a blind, kindhearted piano tuner who takes him in and uses music to free the fighter's long-buried heart.

When Harriet Zapper is hired to find the identity of Karel Duval, and the true heir to the Duval family fortune, a bloody trail of murders leads the Big Zapper from London to the South of France and into a hornet's nest of betrayal and death.