Story: Munna "Bhai" (Sanjay Dutt) falls in love with voice of the Radio Jockey Jahnvi (Vidya Balan). However, due to some misunderstanding, Jahnvi thinks Munna is a history professor and invites Munna to see her family and give them a lecture on history. What should Munna do ...? ...detailed story of Lage Raho Munna Bhai