Set in 1950s Calcutta, মহানগর is a story of emancipation in a changing society. Arati (Madhavi Mukherjee) is a housewife from a traditionalist family, who – in order to support her relatives' lavish demands – goes out to work as a door-to-door saleswoman. Slowly, she discovers her independence.

“I've got it. Film star! You'd be perfect. Dark glasses, lots of red lipstick, and 100,000 rupees per picture. And if it's a Hindi film, we'll all fly to Bombay.”

– Bani