赌王雷天在赌术大赛中因对手“赌花”上官飞花（宫雪花 饰）出千而失利，心有不甘的雷天自杀身亡。雷天在警队中的好友华叔于公于私都有惩治上官飞花的理由，于是请犀牛皮（冯淬帆 饰）召集其他几位福星罗汉果（曾志伟 饰）、大山地（吴耀汉 饰）和花旗参（苗侨伟 饰）参加赌术特训，以期能够战胜上官飞花。雷天之女雷慧琳（冯秀燕 饰）及其替身也一同受训，鹧鸪菜（洪金宝 饰）因受伤不能参加委托少林僧人清补凉代替。众位福星在赌术老师（郑佩佩 饰）和千王（陈百祥 饰）的调教下进步神速。华叔见时机已到，派出众福星和雷慧琳内应外合盗出上官飞花财产，并通过新一届赌术大赛要上官飞花身败名裂……

拍摄外星人入侵题材的电影无外乎从两方面入手：要么笔调轻快，要么手法沉重。其中并无捷径可寻，也不可能草草绕过了事。但遗憾的是《外太空杀人小丑》仍然试图寻找一条中庸之道，于是他们选中了“马戏团”这个中介。想象一下所谓的惊天大阴谋就是一群穿着小丑服的外星侏儒在地球上大肆破坏，用激光射线枪把人类变成喷喷香闪闪亮的棉花糖——除了让人眼花缭乱一番之外，恐怕很少有人能真正进入情节并真正理解。实际上《外太空杀人小丑》是一部具有强烈超现实主义风格的影片，几乎没有什么娱乐性，核心题材也不那么拿人眼球，所以有点不太容易令你坐下来，安安稳稳地把电影看完。而对于大多数人来说，如果一部关于外星小丑的电影拍的一点也不滑稽，那还有什么可看的呢？不过幸运的是，在后来的一大堆类似题材的电影中，这一部算是优秀的了。

This very Kafka-esque film is Keaton's response to the Fatty Arbuckle scandal.[citation needed] Even though the central character's intentions are good, he cannot win, no matter how inventively he tries. He gets into various scraps with police officers throughout the film. Eventually, he unwittingly throws a bomb into a police parade and ends up being chased by a horde of cops.At the end of the film, Keaton's character locks up the cops in the police station. However, the girl he is trying to woo disapproves of his behavior and gives him the cold shoulder. Therefore, he unlocks the police station and is immediately pulled in by the cops. The film ends with the title "The End" written on a tombstone with Keaton's pork pie hat propped on it.One of Keaton's most iconic and brilliantly-constructed short films, Cops was deemed "culturally, historically, or aesthetically significant" by the United States Library of Congress and selected for preservation in their National Film Registry in 1997.

年迈的田美云，终身孤独在自己的老房子里，直到某日，一对年轻夫妻带着婴儿来租房，田美云望着小夫妻手里抱着的婴儿，第一次敞开了大门……有⼀次年轻夫妇把婴儿独⾃留在家里，⽥美云因为听到婴儿哭声，想要照顾邻居的婴儿，美云抱著婴儿时，转忆到⾃⼰的⼩孩⽽性情⼤变，想起了⼩孩死前⼀刻，⽥美云把失去⼀个⼩孩所带来的深层愧疚感影射到另一个小孩的身上。