哈罗德受邀参加一场华服生日派对，所以他和他的朋友必须想出一些华丽的服装。派对进行得很顺利，可是，在黑暗中，过生日的小男孩的蛋糕在一个游戏中被偷了，在这个丢失的蛋糕的谜团中，每个人都是主要嫌疑人。哈罗德能讲零星的线索拼凑起来解出这个谜团，从而挽救这个派对吗？在这场精彩的新冒险中找出答案吧。主角是所有人最爱的狐狸侦探，无法战胜的哈罗德。一个鼓励诚实和分享的趣味故事，一定能成为家庭的最爱。

When Harold is invited to a fancy dress birthday party, he and his friends must come up with some fantastic outfits. The party is going really well but when the birthday boy s cake is stolen during a game in the dark, everyone is a prime suspect in the mystery of the missing cake. Can Harold piece the clues together to solve the mystery and save the party? Find out in this fantastic new adventure starring everyone s favourite fox detective, the irrepressible Harold. A funny story which encourages honesty and sharing, this is set to become a family favourite.