内容简介：
The year was 1937 and Hitler had just walked into Austria. It was also a marvelous year for Clouded Yellow Butterflies...Duncan and Wilfred live in a large old house in Sussex, only ever see their parents on Wednesdays for lunch, and spend their days catching butterflies and dreaming of adventure. When their mother elopes and their already distant father takes up with other ladies, the brothers run away from home. They already have a plan - to go to London and buy a tram they have seen in an advertisement. It costs two pounds. As the Second World War hits England, Duncan and Wilfred, along with their tram, embark on an adventure of a lifetime.