Alia Arora (Alia Bhatt) is an orphan who is adopted by Bipin Arora (Pankaj Kapur) whose wife Geetu Arora (Niki Aneja Walia) and mother Kamla Arora (Sushma Seth) are extremely business minded and have no feeling except for money. Alia is hated by Geetu and Kamla but is loved by Bipin and his daughter Isha (Sanah Kapoor). Alia is also an insomniac who Bipin encourages to sleep by giving dreams drawn on paper but doesn't succeed.

The girls grow and while driving to the palatial wedding place for Isha, Bipin's car is hit by Jagjinder Joginder aka JJ (Shahid Kapoor) driving his motorcycle and abuses him comically, and is later revealed to be the event manager for Isha's marriage. The marriage is being arranged as a business merger between the Fundwanis led by Mr. Fundwani (Sanjay Kapoor) and Aroras. The bridegroom Robin Fundwani (Vikas Verma) is a fitness freak and is obsessed with his abs; he looks at Isha with contempt because she has a thick body. Through some magical and comical moments, Alia and JJ (who is also an insomniac due to loss of his mother in riots) get attracted to each other and finding peace among each other end up sleeping and thus curing their insomnia. Kamla has a sneezing accident and dies. But the Aroras are desperate for the marriage as they are bankrupt and really need the money from the merger of the two families.

Robin, on the other hand, escalates the friction by verbally abusing Isha at many instances leading to Isha breaking her marriage off at the wedding dais and her speech inspires everyone to believe in themselves and their real inner self. Frustrated Fundwani tries to physically force the marriage through and it is revealed that the Fundwanis are bankrupt too. Alia, Isha, JJ, Bipin, and Robin escape from the scene and fly off to a happy ending.