First published in 1962, this is the book that started Dick Francis on his career as a novelist.
Francis was forty-two at the time, a veteran of World War II, and a former steeplechase jockey himself. Virtually all of his novels take place in and around the world of British horseracing. While he repeats the same character only a couple of times, virtually all of his protagonists are the same sort of man--relatively young, intelligent, determined, courageous, and somewhat aloof--at least until the point where they might the right woman and then, often as not, it's love at first sight.
Early on in the course of each novel, the protagonist discovers some glaring injustice and determines to investigate. Inevitably, he antagonizes the wrong person and finds his own health and well-being in grave jeopardy. Often there is some powerful, sinister force, directing events from behind the scene, and our hero must root him out.
In this case, the protagonist is Alan York, an amateur steeplechase rider. He comes from a moneyed family in Rhodesia (now Zimbabwe), and when he's not riding, he works in this father's shipping firm in London.
As the book opens, York is riding in a race alongside his best friend, Bill Davidson, who is riding a horse called Admiral. Davidson and Admiral are the heavy favorites in the race, a "dead cert" to win. But then, at the back of the course, Admiral trips over a fence. The horse goes down on top of Davidson, who will die as the result of the injury. York, riding right behind Davidson, saw something suspicious just before his friend fell. After the race, York goes back to the jump where Davidson fell and discovers that someone had stretched a wire across the top of the jump, causing the horse to fall and Davidson to be fatally injured.
By the time York can get someone in authority to examine the scene, the wire has been removed and there is no evidence that the horse was deliberately tripped. York knows this to be the case, however, and begins his own investigation. He discovers that someone has been attempting to fix races and the deeper he gets into the investigation, the more trouble he finds himself in. Before long, he discovers that he's in a contest of wills against a very dangerous adversary who will stop at nothing to preserve his criminal enterprise.
All in all, it's a good story. As in all of these books, one learns a great deal about the world of British horse racing, and the novel should appeal to anyone who enjoys classic British crime fiction.