七月颱，鬼門開。媽媽匆匆忙忙的帶著豆豆到基隆阿媽家。風雨中，豆豆覺得 這個台灣邊邊上的城市，好像隨時會被吹進海裡，而山崖上破舊的阿媽家一定是第一個滾下去的房子。

阿媽家後院裡破爛的儲藏室是阿媽不准他接近的禁地，裡面堆滿詭異的泡菜罐。阿媽再三警告豆豆不可以碰這些罐子。豆豆沒聽阿媽的話，自從他打開了一個貼了封條的罐子後，黑貓整個樣子就變了，原來他不小心解開了惡靈的封印 。

豆豆闖禍之後，下定決心逃離這個地方。他在路上遇到傻哥阿民，發現阿民在跟一個他看不到的朋友玩。豆豆和他們一起玩得正開心，阿媽卻急得報警了。警察找到豆豆，把他送回家。黑貓趁阿媽趕回家前，告訴豆豆只要讓這個討厭的阿媽哭三次，收破爛的人就會把阿媽帶走，賣阿媽的錢可以買飛機票讓爸爸媽媽回家。黑貓還告訴他只要在眼皮上擦上阿媽的眼淚就什麼都可以看到了。

DouDou arrives at his grandma's in the midst of a typhoon that almost turns Taiwan upside down in the seventh lunar month.Grandma has a black cat that sleeps on the back of a white dog all day long.  She specifically tells him not to touch the pickle urns scattered everywhere in the yard. DouDou does it anyway and the black cat nearby is transformed completely. Grandma says the evil spirit she suppressed escaped. This evil, like DouDou who does not listen to her, is going to stop her from helping the ghosts return to hell. The purpose of the evil spirit is to collect these wondering souls to be his slaves.

One day, DouDou decides to run away from school and leave his grandma forever. The cat tells him that by applying Grandma's tear onto his eyelids, he will have the power to see the invisible friends. Grandma shed her tear when she sees DouDou safely at home. DouDou saves the tear and applies it on his eyelid.