Twenty years ago, an inexplicable mass suicide occurred in the millionaire Yang household. The entire clan hung themselves at the exact same hour, place, and height. Only one member survived. To this day, the case remains unsolved.

Twenty years later, distant relative James inherits the Yang house, moving in with his girlfriend Yo, a dancer who aspires to study in the U.S. To celebrate the engagement, they invite their friends, Yi-Chen and Ah-Tseng, to their new home and stay the night.

As supernatural events begin to take place, James and Yo discover the eccentricities of the house, including a mysterious fourth floor. Delving deep into history, James and Yo find out that the Yang fortune was built with the aid of dead babies fed on blood and refused the opportunity to reincarnate. Raising child ghosts may bring great fortune, but at the same time great doom.

From here on, James and Yo unearth more secrets about the Yang family - and even about James himself - until they confront the evil dwelling on the fourth floor