Two young men try to rob a bookmaker's shop in Malton, but they are frightened off when their gun does not fire. During their escape one of the men, Peter Corcoran, injures his partner Nathaniel Cooper when he test fire the gun in the car. They dump their car in a stream and set out in opposite directions. Cooper hitches a hike with the gipsy - sorry, traveller - Johnny Lee, who is on his way to the horse fair in Aidensfield. Lee hides him and disposes of the gun. The police soon pick up Corcoran, and Lee turns against Cooper when the latter breaks into the Aidensfield Arms against his promise not to do any crimes. Another traveller, Derek Egan, persuades Greengrass to organize a race for travellers and their carriages and allows the old scoundrel to take bets on the outcome in return.

Like many girls Pattie and Sheila Reilly likes horses. One day Pattie takes a ride on a stray pony. An unknown man surprises them and very unwisely fires a shot in the air. The sudden bang startles the horse and makes it bolt. Pattie is thrown off and her scared kid sister flags down PC Walker, who gets both of them to Dr. Trent's surgery. He also has his own, more romantic reason to see the attractive doctor. When Walker tries to find both the owner of the pony and the shooter he suddenly finds himself investigating a series of horse thefts. His life is not made any easier by Joyce Jowett, who complains to the police about a bad smell and noisy lorries from the house at the end of her road. Sergeant Miller has referred her to the town hall because it is not a police matter, but the battleaxe pesters the life out of Walker instead. Aunt Peggy gets mad at Oscar Blaketon for barring her and David from the Aidensfield Arms for playing poker.