It's Christmas in Welford and at Mandy's school new boy Oliver Morgan has come up wth a great idea. He's going to set up a 'hamster holiday camp' for all those whose owners are going away for Christmas. Mandy and James muck in too, and it looks as though Oliver's parents loft conversion will be the hamsters' holiday home. Everything's working out brilliantly! Oliver has nine hamsters to start with, but when one of them gives birth, that makes five more baby hamsters, too. They're cute, but quite a handful. Then disaster strikes, the roof of the loft is leaking, and the hamsters all need rehousing straight away! Poor Oliver feels terrible. What will he do? Then Mandy has a brainwave. There's one group of people who won't be going anywhere at Christmas - the church choir! But will they be willing to hamster-sit for a few days?