Amy's cows have escaped and it looks as if the fence has been cut. Norman, Dennis, and Polly suspect Grainger is to blame. Later, the whole village attends a lecture where Cyril Jenkins shows them a series of posters of people who may be spies in disguise, but one poster in particular startles Norman, Dennis and Polly; an image of a woman in half a Nazi uniform and half normal clothing stays in their minds. Meanwhile, in the present, Norman decides to track down Polly.