Her Majesty's Ship, The Indomitable, is sent to investigate the mysterious disappearance of Doctor Cyrus Grant whilst journeying to Earth's dead satellite. The crew soon discover that Luna is not so lifeless after all... An alien weapon manned by enemies of the Empire; strange creatures hiding in the lunar catacombs; a lost civilisation with technology beyond the wit of Earth. Captain Nathaniel Blake and lunar expert, William Brooker, must brave all these and more to rescue the missing scientist and his niece. New friends and old enemies play their parts as the two men uncover exactly what the lunar inheritance means to the future of the British Empire, and even Earth itself...