'For a few moments this afternoon, it rained on the moon...' An astronaut in full spacesuit appears out of thin air in a busy shopping centre. Maybe it's a publicity stunt. A photo shows a well-dressed woman in a red coat lying dead at the edge of a crater on the dark side of the moon - beside her beloved dog 'Poochie'. Maybe it's a hoax. But as the Doctor and Amy find out, these are just minor events in a sinister plan to take over every human being on earth.