Major Ram Prasad Sharma (Shahrukh Khan) yearns to see the ambitious project Mission Milaap become a reality. A mission that will prove to be the dawn of a new tomorrow! Where long standing enmity between two countries will begin to see its end. But some forces do not want that dawn to come. One of them is Raghavan (Sunil Shetty) who will do anything to prevent the strategic move. For this reason his devious shadow looms large over General Amerjeet Bakshi's daughter Sanjana (Amrita Rao), whose life is in danger.
Every drop of Ram Prasad's blood glistens with the shine of pride for his country and he will not allow dark actions to create an eclipse in its bright future. To protect Sanjana, he goes to her school as a student indeed 'Back to School'! Here fun and frolic conceal his real intent.
Will anyone here guess that he has just lit funeral pyre of his martyr father Brigadier Shekhar Sharma Naseeruddin Shah). The ashes have emerged but the fire has not subsided, for he has to fulfill his father's last wish. Strangely, the fulfillment of his wish also lies in this very school completing this mission will be no easy task. For it involves intense emotions and long standing misunderstandings.
These two missions are now his life-blood. The weapon of one mission is Gun and that of the other is Love. But the road to both is that of Truth. The only option is victory. The only man is Ram Prasad Sharma. And the only mantra is Main Hoon Na!