影片讲述了美国的一个小镇上出现了一个离奇的事情，那就是镇上的小孩总是莫名其妙的丢失，人们在总结之后发现了一个规律，那就是每每当身上出现小丑的时候，孩子就会莫名其妙的消失。

为了抵抗这些小丑，人们组成了一个联盟，联盟当中一共是7个人，这7个人开始针对小丑展开了一系列的复仇和抵御计划。最开始人们实行的是宵禁计划，也就是在夜幕降临的时候，整个城市就会处于宵禁状态，包括大人和小孩都不能上街。随后人们发现这个方法没有任何用处，小孩还是莫名其妙的丢失。这时候一个小学生比利为了寻找自己弟弟丢失的真相，展开了自己的调查。调查之下发现这个小丑存在已经超过上半年的时间，并不是一个真实的存在，更像是一个超自然现象。

The film tells about a strange thing happened in a small town in the United States, that is, the children in the town are always missing inexplicably, and people are summing up Later, I discovered a rule, that is, whenever a clown appears on the body, the child will disappear inexplicably

In order to resist these clowns, people formed an alliance, there are 7 people in the alliance, and these 7 people started a war against clowns Series of revenge and defense plans. At the beginning, people implemented a curfew plan, that is, when night falls, the entire city will be under curfew, including adults and children are not allowed to go to the streets. Later, people found that this method was useless, and the child was still lost inexplicably. At this time, Billy, a primary school student, started his own investigation in order to find out the truth about his brother's disappearance. Under the investigation, it was found that this clown had existed for more than half a year, and it was not a real existence, but more like a supernatural phenomenon.