Nabakumar, a young gentleman from Saptagram, got lost in a forest while returning from pilgrimage in Gangasagar. He met a Tantric sage who trapped him, intending to make him a sacrifice to goddess Kali; but was later freed secretly by Kapalkundala, the sage’s foster-daughter.
She, at once, fall in love with Nabakumar and with the help of a village priest they got married on the next day. The priest urged Nabakumar to take Kapalkundala away from her wicked foster-father and also showed Nabakumar his way to Saptagram. Nabakumar returned home with his newly-wed wife Kapalkundala, now re-christened as Mrinmoyee.
The sage, on the other hand, got annoyed at Kapalkundala’s betrayal and began to plot his revenge. In the meantime, Nabakumar met Padmabati, his first wife, who was converted to Islam by his father, making Nabakumar to desert her. Padmabati, now renamed as Motibibi, expressed her love for Nabakumar, but he refused her.
Later the sage came to Saptagram and met Motibibi. The sage wanted to kill Kapalkundala, but Motibibi wanted to separate her from Nabkumar only. They made a plot to prove Kapalkundala unfaithful. Padmabati called Kapalkundala to meet her in a nearby forest and she, herself, came there in a man’s disguise.
The sage showed Nabakumar that Kapalkundala came out at night to meet a ‘man whom she loves’. Then the sage made the angry Nabakumar bring Kapalkundala to the sacrificial ground where Kapalkundala revealed the truth to him. Nabakumar came to his senses and he asked Kapalkundala to come with him to his home, but she refused and jumped into the river. Nabakumar also jumped into the river to save her, but both of them were lost.