When Sayaka leaps off the balcony to her death at her own housewarming party, all her friends are left in shock. Conviced that her sibling would not have committed suicide, Sayaka's elder sister, Mariko, takes it upon herself to investigate the reason behind the sinister death and soon learns the history of Apartment 1303: Where a love-hate relationship between former tenants - a mother and daughter pair - has now turned into a tale of horror.