It's winter term at the Chalet School, and Emerence Hope, Len Maynard and the rest of lively Inter V can't wait for the fun to begin! But the thrills of skiing and the annual pantomime are forgotten when Joey Maynard announces that the Chalet will soon be twenty-one years old, and everyone must prepare for the greatest celebrations in the school's history. Suddenly there are a million and one plans in the air, but everyone is amazed when noisy Inter V come up with the most exciting scheme of all...