When the festive season arrives at Larklight, so does some unsettling news. A sinister-looking cloud is fast approaching the outskirts of the Known Universe. The closest planet, Georgium Sidus, has but two human inhabitants: the missionary Rev Cruet and his daughter Charity: most recent communication: 'Great danger - imperative that-'.
And so, aboard a Naval Gunship, Art, Myrtle and family, bravely go where only one man and his daughter have gone before, to determine the nature of the menacing cloud and rescue the Cruets.