The seventh lunar month in the Chinese calendar is the ghost month. DouDou? goes to stay with Grandma on the lunar 1st of July, the day the ghost gate is opened. Grandma performs Taoist ceremonies for the deceased and communicates with ghosts. One day, DouDou? accidentally lets the devil out of an urn. The devil possesses a sleepy house cat and tells DouDou? that he can see invisible friends by applying Grandma's tears into his eye-lid. But he must sell his grandmothers soul. Little does DouDou? know that this is part of the devil's plot to eat all of the ghosts...
