Snehmoy and Miyage are pen friends who exchange wedding vows through letters. Fifteen years pass but they never meet. Yet the bond of marriage is strong between them. This unusual relationship comes under a cloud when a young widow, Sandhya, comes to stay with Snehmoy along with her eight-year-old son Poltu. Snehmoy and the little boy bond and the arithmetic teacher discovers the joy of palpable bonds and fatherhood. There develops an inexplicable thread of understanding with Sandhya too. But Snehmoy remained loyal to his unseen Japanese wife.

The film is based on the real life murder mystery of Sheena Bora. Bollywood actress Mahima Chaudhry makes her debut in Bengali film as Ishani Banerjee, a character based on Sheena's mother and alleged murderer Indrani Mukherjea. Riya Sen will play the part of Rina Bardhan, inspired by Sheena Bora. Media baron Peter Mukherjea, Sheena's stepfather, will be portrayed by Sudeep Mukherjee.