Very jealous of the Duke of Desborough's prize race horse "Clipstone," Major Roland Mostyn schemes to destroy his rival and thus obtain possession of the animal. After framing the duke's wife Muriel in a false adultery suit which results in divorce, Mostyn ruins the young duke at cards, thus forcing him to auction his horse in order to pay his debts. Muriel, heartbroken by the separation, persuades her old friend Captain Streatfield to purchase the horse and enter him in the derby. Mostyn bets all his money on his horse and attempts to fix the race but his plot is discovered and Clipstone wins the contest. After Muriel's innocence is proven, Mostyn's villainy towards the duke is finally stopped and the couple is happily reunited.