阿偉（黃河飾）是一個房屋仲介經紀人，認真工作希能與電臺播音員女友怡君（許瑋甯飾）早日結婚。有一天，與他同住的奶奶（劉引商飾）失蹤了…。詭異的是，家裡打掃過了衣服也洗好了，還替阿偉煮了早餐，但就是不見奶奶的蹤影。毫無頭緒的阿偉逐漸感到焦急，他打開鄰人阿水嬸的相機，竟看到其中一段出遊的影片中，有個詭異的身影跟在奶奶背後，像是個穿著紅衣的小女孩，阿偉打從心底感到不寒而慄，沒想到詭異的事情，開始接二連三地發生…。

Based on true events and long-circulating urban legend in Taiwan. Weiis nowhere to be found one day before his grandma returns from her ownstrange missing incident. Wei's girlfriend desperately searches forhis whereabouts and finds that it is the horrifying mystery of thelittle girl in red that has followed and haunted them all along.