Karthik's boss treats him like dirt. Shonali (Deepika Padukone), his colleague who he secretly loves, isn't even aware that he exists. In a nutshell, Karthik (Farhan Akhtar) is a loser. He knows it and accepts it. Karthik believes his life can't get any better. But then, suddenly one night, it happens: the phone rings. And Karthik speaks to someone he never thought he would. The man on the other end of the phone line also claims to be Karthik. He tells Karthik, the loser, that he's here to change his life for better. Karthik accepts the phone in his life and soon it becomes his guide, his mentor, his friend, his guardian. And most importantly it becomes the ticket to the love of his life, Shonali. Thereafter, Karthik's life changes in ways he hadn't imagined.