Summer the Holiday Fairy has got her work cut out. Jack Frost has moved to Rainspell Island for the summer and it's a very different place to when Rachel and Kirsty visited in the first series. Now there are no tinkling ice-cream vans or sailing boats. There's not even any sand on the beach! Jack Frost has taken it all to build his giant sandcastle. There arethree special shells, that control the holiday atmosphere. Summer the Holiday Fairy needs Rachel and Kirsty's help to get them back.