Returning to Lakeville at the height of a raging snowstorm, Hop and Tank narrowly escaped a dangerous crash with another plane, but managed a successful landing in the snow. They were greeted by Gail, who informed them that Aunt Agatha and young Christopher Cross were in Lakeville attending a party in celebration of a new bell for the town hall steeple. Shortly before midnight however, Aunt Agatha phoned, with news that something dreadful had happened...