Bajirao Ballal (Ranveer Singh) is appointed by Chhatrapati Shahu Maharaj (Mahesh Manjrekar) as Peshwa. The selfless crusader dreams of a unified Hindu kingdom. One day, a beautiful half Rajput, half Muslim fighter-princess Mastani (Deepika Padukone) from Bundelkhand comes to Peshwa Bajirao in search of help for saving her kingdom. Bajirao goes to Bundelkhand with her in order to save her kingdom and a tender bond of love starts blooming between Peshwa Bajirao and Mastani. Peshwa Bajirao goes to his kingdom after the victory of Bundelkhand in the war.

Mastani, lost in love of Peshwa Bajirao, decides to go to Pune at Peshwa Bajirao's kingdom. As expected, the family of Peshwa Bajirao and other people deny to accept Mastani as Bajirao's second wife and the further tale happens.