One evening, Lily is playing on the beach. And who should float in, but LOTS of polar bears! Lily is excited to welcome them home for dinner (of fish fingers and ice cream, of course) and to have them stay for a sleepover. Lily has even more fun with the bears when they go swimming, ice skating, and visit the fun fair - and it soon turns out that polar bears are really quite good at a lot things, becoming polar bear postmen, opening ice cream parlours, and even becoming astronauts!