Manasi is the story of Devi, Amit, Neela. Amit meets Devi and her elder brother Moloy during a train journey. Amit is a jovial boy who befriends Moloy. He becomes close to his family, Devi and Devi's friend Neela. He finds out that Devi remains quite and depressed as Vikram, her love died in an accident. Amit's jovial presence helps Devi get back to normal life. Neela develops feelings for Amit and so does Devi. Amit proposes to Devi the day he is about to leave her home. Devi says that she can't accept his proposal as she is a murderer. She confesses she killed Vikram. Devi is arrested. Amit turns out to be a IPS officer sent to investigate Vikram's death. Amit further investigates the case and it's revealed that Vikram was a characterless rich spoilt brat who tried to rape Devi and the scuffle between them led to his accidental death. Devi is released and they are happily united.