Cataract follows Mia, as she accompanies her girlfriend, Dani, and Dani’s ghost-hunting friends, as they investigate a house where just three years prior, a double-murder suicide occurred involving one of their classmates. They try to reach out to their deceased classmate, Ruby, who answers them and reveals the truth about her death. However, Ruby has become vengeful from her unjust death, and seeks her revenge on anyone who tries to enter the house, taking them one by one.