While visiting a dying racing columnist named Valentine Clark, Tom Lyon is mistaken for a priest by the confused old man and forced to hear his confession. Since the names mentioned by Valentine are totally unfamiliar to Tom, he disregards the confession as merely the product of Valentine's delirium.
Tom is directing a movie nearby which is inspired by a famous unsolved murder case from the past. Sonya Wells, the wife of trainer Jackson Wells, had died mysteriously of asphyxiation. Sonia was the sister-in-law of Rupert Visborough, a prominent member of the Jockey Club. The careers of both Wells and Visborough were ruined by the suspicion of murder. Valentine had known these two men as well as Sonia and several of her friends.
As the filming progresses numerous attempts are made to stop Tom from completing the project and perhaps solving the mystery of the killing. One of the actors is slashed while riding on the heath by an unknown horseman.Valentine's sister Dorothea is attacked and her house is ransacked. Tom is stabbed in a crowd. By the time Valentine's nephew is killed, it is very clear that the murderer is after Valentine's books and notes which are now in Tom's possession. In order to catch the killer, Tom does some research on exotic knives and then takes the necessary risks to lure him out of hiding.
I consider WILD HORSES to be one of the better crime novels written by Dick Francis. The book also contains some interesting glimpses into British filmmaking.