MISSION MAJNU is the story of an Indian spy in Pakistan. In 1974, India successfully conducted nuclear tests, shocking the world. Pakistan’s Prime Minister Zulfikar Ali Bhutto (Rajit Kapur) is upset. At the advice of ISI Chief Maqsood Alam (Shishir Sharma), Pakistan decides to invite Abdul Qadeer Khan (Mir Sarwar),… a nuclear scientist based in the Netherlands. A Q Khan is given the responsibility of building an atomic bomb and Pakistan plans to secure its parts from the black market. RAW’s chief R N Kao (Parmeet Sethi) learns that Pakistan is upto some mischief. With the approval of the Prime Minister of India (Avantika Akerkar), he informs his secret agent in Rawalpindi, Amandeep Singh aka Tariq (Sidharth Malhotra) to find out more details and the whereabouts of the atom bomb facility. Tariq is working as a tailor and has successfully created his image of a good-natured simpleton. Hence, no one has the slightest doubt that he’s a spy. He falls in love with Nasreen (Rashmika Mandanna), a blind girl and both get married. Tariq works at the tailor shop of Nasreen’s uncle Momin (Manoj Bakshi) and they often get the order of stitching clothes for the Pakistani army. Tariq uses this opportunity to speak to the Pakistani brigadier and finds out information about the bomb and who is the scientist who’s spearheading it. His mission isn’t easy as he needs to be very careful that the Pakistani army or the intelligence does not find out the truth about him. Moreover, he has a tragic past. His father was caught selling sensitive defence information about India to Pakistan. Tariq’s handler Sharma (Zakir Hussain) in Delhi leaves no opportunity to remind him that he’s the son of a traitor. Moreover, Tariq is not expected to marry and fall in love. Yet, he is crazily in love with Nasreen and they are also expecting a child. What happens next forms the rest of the film.