"Sumpa ng Mangyan" is a Tagalog horror animation that revolves around a curse placed by a Mangyan tribe through the use of kulam (witchcraft). The story follows Jessa, a young woman who unknowingly offends a Mangyan elder during a trip to a remote village in the mountains. After the incident, strange and terrifying things begin to happen in her life—she experiences unexplainable illnesses, disturbing nightmares, and eerie visions.

As Jessa’s condition worsens, her family seeks help from various doctors, but no medical explanation can be found. Desperate for answers, they consult a local albularyo (healer), who reveals that Jessa has been cursed by the Mangyan elder through a powerful kulam. The curse is tied to a deep spiritual offense, and it can only be broken by seeking forgiveness and performing a dangerous ritual in the mountains where the curse originated.

Jessa and her family embark on a journey back to the Mangyan village to confront the elder and lift the curse. Along the way, they must navigate through supernatural obstacles and confront the spiritual forces tied to the curse. In a tense and dramatic climax, Jessa faces the consequences of her actions and must prove her sincerity to the elder to break the curse before it consumes her completely.

"Sumpa ng Mangyan" explores themes of respect for indigenous cultures, the consequences of offending spiritual traditions, and the power of forgiveness. The animation blends Filipino folklore with supernatural horror, showcasing the mysterious and potent force of kulam in traditional Mangyan beliefs.