To the Jockey Club, the racing world would be a better place without Julius Apollo Filmer. An expert in corruption with a devastating line in witness intimidation - and a slippery character to put behind bars. Baffled, they call in undercover security agent Tor Kelsey to keep an unflinching eye on Filmer and his associates. A mission that takes him from the finest of English racecourses to the wild Canadian interior - on a luxury transcontinental train journey to end them all. On board, a troupe of actors are playing out a murder mystery for the amusement of their diamond-studded passengers. Ideal cover for a secret investigator with secrets of his own. And better still for an ice-cool blackmailer for whom murder is just one of many options …