Stevie, Carole, and Lisa are going back to the racetrack. They can't wait to help cool off their friend's sleek Thoroughbred racehorses by walking them. They'll even earn a little money for doing something they'd do for free! What could be better? Then the girls spot an official somewhere he shouldn't be, taking money from someone he shouldn't be talking to. Worse, the official sees the girls and knows they're on to him! Now the girls are in danger. More than one kind of race is going to be run—the Saddle Club girls must race for their lives!