In 1947, Vinayak Rao tells his 14-year-old son Pandurang about the Goddess of Prosperity. She is the symbol of unlimited gold (wealth) and grains (food) and the earth is her womb. When the universe was created, she gave birth to 160 million gods. Hastar, her first and most beloved offspring, was greedy for all her gold and food.
Hastar managed to acquire the gold from the goddess but the other gods attacked him just as he was about to acquire her food, but the goddess saved him on the condition that he could never be worshipped and would be forgotten by history. For years, Hastar had been slumbering inside his mother’s womb.
However, the residents of Tumbbad, where Hastar has been trapped in his mother’s womb, defy this ancient taboo and build a temple dedicated to Hastar, earning the ire of the Gods and curse the village, causing a nonstop downpour of rain over it.
In 1918, in Tumbbad, Maharashtra, Vinayak’s mother serves the local lord, Sarkar, in his mansion. This includes offering him sexual services in the hopes to acquire a single gold coin kept with his Hastar statue. Meanwhile, at their home, Vinayak and his younger brother Sadashiv worry about having to feed the monstrous old woman, Vinayak’s great grandmother, chained up in a separate room. Sarkar later dies and the mother proposes leaving Tumbbad for Pune. Vinayak insists on finding the treasure that is rumoured to be hidden somewhere in the mansion. Sadashiv gets badly hurt after falling from a tree, forcing his mother to take him for help. She tells Vinayak he will have to feed his grandmother that night. She also warns him that if the old woman wakes up, he should invoke the name of “Hastar” to make her sleep. Meanwhile, Sadashiv dies on the way to the doctor.