小镇盗窃案频频发生，一只梦想成为大侦探的猫咪为了找出真凶决定离家出走。旅途中的她遇到了一只自认风度翩翩的公鸡，一只梦想成为马戏团明星的驴，一只仇恨人类的守门狗。四只小动物历经磨合，即将找出真凶时，却被误认为是偷窃真凶。他们该如何证明清白，如何守护友谊和梦想……
万圣镇的各位鬼怪，已经习惯于在每年万圣节那天出没搞作一下，他们是彻头彻尾的少根筋的生物，只晓得如何吓人。而南瓜王子杰克，是非常与众不同的一个。他已经厌倦了带给人们惊恐的玩意，一心想做出某些改变。偶然一次打开了圣诞镇的大门，让他眼前豁然一亮，杰克心中燃起了要带领兄弟制造圣诞欢乐的决心。
At a used car lot, Mr. Magoo is intent on buying a car for his nephew Waldo. He is slick talked into buying an old clunker thanks to a shifty salesman but he drives it off anyway. Unfortunately, the myopic Magoo drives off a pier and under the ocean where he mistakes the various aquatic surroundings such as fish, sunken boats, and seals for other cars, dilapidated mansions, and a horn happy driver respectively.
本片讲述了随着钻石的神秘失踪，伦敦警方组织了很多侦探去查找罪犯，汤姆和杰瑞就是一对组合。棘手的案件让这对猫鼠痛苦不堪，只能寻求世界上最棒的侦探的帮助，他就是夏洛克·福尔摩斯先生。
