The story follows Sulastri and Soedjiman, a wealthy couple desperate for a child. Sulastri makes a . She gives birth to twins: Kumala, a kind but physically disabled girl, and Sumala, who is killed at birth by her father because she appeared "deformed". Years later, the spirit of Sumala returns to possess Kumala, seeking gruesome retribution against the villagers and family members who mistreated her twin. Sumala Movie Review | Common Sense Media

Fans have drawn direct parallels between Sumala and the legendary Tamil horror film Eeram (2009) – specifically the element of water and curse. Others compare the tragic backstory to the 2022 hit J Baby , though that film was a drama. The visual style of Sumala’s ghost is also being compared to the eerie child spirits in Andhaghaaram (2020).