Boom, a young Thai woman working at a country club, becomes involved in a secret affair with the married man Prathan. The relationship ends up bearing a pregnancy, and Boom must decide how to handle the situation. Prathan initially reacts with hesitation, asking Boom how much money would be enough to keep her quiet, and Boom names a substantial amount. After he pays, he seems to back away, promising he will not abandon her.
Night falls, and Boom wakes to a disturbing scene: Prathan is speaking with his friends behind the window of his beach house. He bluntly explains that, given the money paid, he now has the right to share her with his circle. With a video camera rolling, Prathan’s friends pursue Boom across the room and onto the beach, where she is humiliated and subjected to what appears to be a gang-rape. The moment makes clear that Prathan never intended to stay with Boom after the pregnancy.
An ultrasound at the hospital confirms that the baby has serious congenital abnormalities. Boom, meanwhile, spots Prathan dining at a restaurant with his family from a second marriage, including Kamala as his wife. A friend urges Boom to consider abortion, but she refuses, determined to raise the child even if Prathan won’t acknowledge paternity. The attending OB/GYN warns that the baby’s quality of life could be severely limited, yet Boom presses on. She interrupts the family celebration at the restaurant to demand more money, and Prathan, embarrassed, drags her outside, slaps her, and tells her not to come near his family again, tossing a wad of cash as if the matter is closed.
Fuelled by anger, Boom seeks out a black magic shaman Shaman to exact revenge not just on Prathan, but on his friends and his entire household. The ritual unleashes a brutal chain of violence: the second eldest son shoots his girlfriend and his younger sister before turning the gun on himself; Prathan is later found dead at his beach house by his newest mistress. After the deaths, Boom is told that offerings of coffins are needed to calm the vengeful spirits, and she dutifully donates them as instructed.
In the wake of the ritual, Boom visits a temple and leaves with a chilling sense of a bargain fulfilled. Walking away, she briefly encounters the ghosts of her victims and is tragically struck by a car, losing the baby. Kamala inherits the wealth, moves into the house with her four children, and Boom amplifies her curse to claim the inheritance by removing the new family as well. A young newspaper reporter grows increasingly suspicious, and Boom makes sure he dies too, all while the spectral presence of Boom’s dead daughter lingers around the home.
The story closes with only the youngest son, Bon, and the eldest daughter, Nan, surviving the massacre. Boom’s arc culminates in tragedy as she ascends to the hospital roof and falls to her death after glimpsing her daughter’s ghost, leaving a legacy of ruin and unanswered questions in her wake.
