Kalki Koechlin

Three friends decide to turn their fantasy vacation into reality after one of their number becomes engaged. At the beginning of the film, Kabir (Abhay Deol) proposes to Natasha (Kalki Koechlin). Their families meet at the engagement party. At the party, Natasha learns that Kabir is planning a three-week bachelor road trip to Spain with his school friends Imraan (Farhan Akhtar) and Arjun (Hrithik Roshan). Kabir explains that the three have a long-standing pact, and that during the road trip, each of them will have to pick an adventure sport, which all three will try together.

Naina (Deepika Padukone) is a shy and nerdy medical student. She studies constantly and always tops her classes. An encounter with an old classmate, Aditi (Kalki Koechlin), makes her realise that she wants more from life than high marks. She makes an impulsive decision to follow Aditi on a commercial hiking trip into the Himalayas, up to Manali. During the hike, she renews her friendship with another former classmate, Kabir "Bunny" Thapar (Ranbir Kapoor). Bunny is a handsome charmer whose dream is to travel the world. He does not plan to marry or settle down.