Deewanapan is the story of Suraj Saxena (Arjun Rampal) lives in a small hill station Dalhousie with parents (Om Puri & Smita Jaykar) and a sister Asha (Amita Nangia). This middle class guy falls in love with a rich, girl Kiran Choudhary (Diya Mirza), who has come to Dalhousie with a bunch of friends for an outing. After the holiday trip is over, he returns back. but suraj is not abl to take Kiran out from his memory. His sisters gets married & his father gets transferred to Mumbai. After admission into a college in Mumbai, Suraj becomes very popular due to his excellent show as a football player. Luckily he also gets to meet Kiran and the love again blossoms. When Kiran's father Ranvir Choudhary (Vinod Khanna) knows about it, he doesn't approve that a poor man loves his daughter, he insults Suraj in front of the so called high society people in a gathering. And after the embarassment, he threatens Suraj to leave the city. But under the craziness of love (deewanapan) Suraj stays in city only to get his love Kiran. But the powerful Ranvir does all the harassments not to Suraj but his innocent parents. What will Suraj do ? will he still fight for his love? or will leave the town for sake of his parents ?