After receiving a mysterious warning, amateur detective Philo Vance drops in on the Gardens. Floyd Garden and his friends are avid horse race gamblers and are throwing a party of sorts around the Rivermont Handicap. His cousin, Woode Swift, has staked his entire fortune on a horse named Equanimity. Swift is spared the grief of Equanimity’s loss by receiving a bullet to the head ten minutes before the race.
It was framed as a suicide, but Vance at once spots the tell-tale signs of murder. But who among the several guests is guilty? Vance remains vague till his melodramatic reveal at the end, but the clues given quickly narrow the case down to two suspects, and the book isn’t two-thirds done until any reasonably attentive reader will have arrived at the culprit. All the fun of detective novels is in trying to solve the mystery yourself, but this one is simply too easy.