After a job as a house-sitter in a high-tech mansion ends in disaster due to a pesky insect, Trevor Bingley has traded the stressful world of house-sitting for the quieter life of a school caretaker. Then he receives a lucrative offer to look after a luxury London penthouse for the holidays. But on the last day of term, when no one comes to collect the baby Jesus from the school nativity scene, Trevor finds himself with another small and unexpected companion.