Rajiv Malhotra (Sachin Khedekar) meets the evil Charles (Zakir Hussain) in the flight and helps the authorities in getting him arrested. At the same time, Rajiv's wife Ankita (Prachee Shah Paandya) gives birth to twins. Charles gets arrested in the hospital where Ankita had her delivery and he runs away with one of the twins. Rajiv and Ankita presume that child to be dead due to certain circumstances and they move to London with their other son. This son, Prem (Varun Dhawan), grows up as a shy and docile person who can be easily bullied. His brother Raja (Varun Dhawan) grows up in Mumbai's Versova and is the opposite of Prem â€“ he is outgoing, brash and bullying him is next to impossible. However, Raja falls in trouble when he fights with Alex (Vivan Bhatena) and injures him badly. Alex is incidentally the son of Charles and is also quite villainous. Raja and his sidekick Nandu (Rajpal Yadav) escape to London as a result. In the flight, he meets Alishka (Jacqueline Fernandez) and both fall for each other. Prem on the other hand starts dating Samaira (Taapsee Pannu) who learns music from him. But strange things start happening to both Prem and Raja as soon as the latter lands in London. The twins suffer from a peculiar problem â€“ if one feels pain, the other shall also experience the same feeling and both even replicate each other's actions, depending on distance. Both go through a series of hilarious incidents as a result. What happens next and how the madness unfolds is what the rest of the film is all about.