Sergeant Barker and his sidekick, Constable Stephens, investigate a 'Peeping Tom' thieving underwear in the dead-end town of Dunbury. Barker and Stephens aren't used to much police action in Dunbury - crosswords, cups of tea, and petting the station cat is about as exciting as it usually gets for them - so they waste no time in launching a full investigation. Knocking doors around town to chase up leads, they find themselves on the doorstep of the troubled Kelly family, but will they catch the culprit?