After being hurt in a fall during a race, champion steeplechase jockey Sid Halley decides to investigate a number of strange accidents of Seabury race course. Sid's former father-in-law thinks Howard Graves, an entrepreneur looking to buy the course and build a large shopping complex on the site, maybe trying to lessen its reputation so as to reduce any purchase price. Sid doesn't think he'd make much of a detective but decides to give it a go. Slowly, he pieces together Graves' plan and soon uncovers an inside man at the racecourse.
In the high-stakes sport of horse racing, the rich only want to get richer. As Sid learns to use his new prosthetic hand, he and Chico investigate why a winning horse keeps losing to long shots. They uncover race fixing, blackmail, and murder and realize that nothing is what it seems.
When a valuable horse dies in a suspicious road accident, Sid and Chico are hired to investigate a possible insurance scam. They unearth an international swindle, meet a beautiful woman who bets on a losing mare, and travel to Milan to discover the truth.
A long shot comes home first, and a bookie loses big. Sid and Chico discover a complex scheme for fixing bets, a web of shady outside interests, and a thug who kills to guarantee silence. Soon Sid's own life hangs in the balance.
When a famous retired racehorse is kidnapped, no ransom demands are made. Sid and Chico are called on to find the horse and bring him home. Meanwhile, a reporter learns that the crime could be linked to a man in prison who claims he's innocent. A publicity stunt will turn to tragedy unless Sid acts quickly.
Horses favored to win are running poorly, but why? When Sid discovers an empty syringe outside the stable of a promising colt, he asks a brilliant and beautiful friend at Cambridge to help him find answers. As Sid and Sally race to prevent disaster, their lives are on the line.