LEON SPARKS is from Mars. When, in the summer holidays, Leon invites his friends to a secret base on the Moon for a week of Space School, no-one could have guessed this would mark only the beginning of their latest adventure. After their Moon base and the Earth are attacked by a swarm of asteroids directed from Mars, Leon and his friends find themselves on a spaceship bound for Leon's home planet, where a new ruling elite, hostile to Earth, has taken over.