The story takes place in the 18th century.
A pirate ship commanded by Captain Bernardito Luis El Gorro captures a passenger vessel in the Indian Ocean: the heir to a count’s title, Frederick Rayland, who is traveling to England from Calcutta, and his fiancée, Emily Hardy. Bernardito’s assistant, Giacomo Grelli, nicknamed “the Leopard,” appropriates Rayland’s documents and arrives in England under a new name. Emily travels with him as his fiancée to save her fiancé’s life. Captain Bernardito and the real Rayland end up on an uninhabited island.
Further events shift from country to country: England, Italy, Spain, the African coast, the North American colonies. Among the heroes who multiply page by page are the Luddites, Jesuits, pirates, slave traders, Indigenous peoples… The novel also tells about the past of the main characters. Giacomo Grelli turns out to be the illegitimate son of a noble Italian gentleman. And Bernardito is a Spanish grandee who was unjustly sentenced, escaped, took revenge on his offenders, and then became a pirate.