Kabrastan (2000)

A married man has an affair with a married woman in this woman's house. When the woman's husband unexpectedly shows up with a bottle of acid, which he plans to throw on his wife's face, disfiguring her for life. The woman's lover quickly responds by taking out a gun and shooting at the bottle of acid, which is smashed and lands on the husband's face, disfiguring him. The man then shoots the husband, until he is dead. Both the woman and the man, bury the dead, disfigured body, and go about their respective tasks, not knowing that they have unleashed an unstoppable evil force that will spring forth to bring death and destruction to the man, his brothers, and his wife.