W.P.C. Ackland and P.C. Smith attend a local gypsy campsite where residents are complaining. A social worker has a Place Of Safety Order on one of the gypsy children, Theresa Beecher, who was reportedly beaten by her parents. When the girl and her parents lock themselves in the caravan, Smith has the idea of towing the caravan to the station. A youth is found in possession of stolen credit cards, and the owner is located and confirms he was attacked and robbed the night before. He is about to do an identity parade, but his wife admits she was the one who hit him. The gypsies make a run for it, but when the little girl is taken into care, it is found the Beechers have swapped their daughter with another little girl.