Harry is an eight-year-old boy growing up in Ireland with his dis-spirited widowed mother and older brother. He is bullied in school, and his only real friend is his dog Max. His great joy and obsession are the Flash Gordon episodes he watches on TV, and he believes that he and his dog are really from the planet Mercury. Over time, Harry learns to appreciate the value of his family, but he never ceases to think of himself as the boy from Mercury.