Plot

Prem and Raja are twin brothers who are seperated at birth but are uniquely connected to eachother via their reflexes. They reunite as adults and set out to take down the underground smuggling world.

Two brothers (twins) born to an honest businessman are separated at birth when their father exposes a smuggling racket and a king pin. One of the brothers is thought to be dead but only resurfaces stronger after living life on the streets to reunite with his family over a sequence of events and twist of fate. Genetically bound by reflexes both the brother's lives interlink in strange ways and a comedy of errors. They eventually come together to destroy the smuggling nexus and save their family from a downfall that awaits them.—Khush Sidhu

Rajiv Malhotra is returning to his home to be with his pregnant wife Ankita. On flight he befriends Charles unaware that he is a smuggler. Ankita gives birth to twin boys and Charles comes to congratulate him. But Rajiv comes to know bout him and calls the police in the mishap Charles runs away with one one of the twin. Police arrest him but he claims the kid died in a blast. Rajiv Malhotra shifts to London with Ankita and his son Prem for safety reasons where as the other twin is alive and grows up in the slum of Mumbai by the name of Raja. Will destiny bring the lost twins together someday ?—alex.mjacko@gmail.com

Rajeev Malhotra (Sachin Khedekar) is returning to his home to be with his pregnant wife Ankita (Prachi Shah). On flight he befriends Charles (Zakhir Hussain) unaware that he is a smuggler. Charles uses Rajeev to smuggle diamonds into Mumbai as he was himself on the watch-list of Mumbai customs. Rajeev was going to meet his pregnant wife in Hospital. Ankita gives birth to twin boys. At birth the twins were joint at the arms and were separated, so they share reflexes (which is a one in 80 Lakh phenomenon), and Raja was the strong one and Prem weak. The doctor also predicted as one becomes weak, the other will become stronger. Charles comes to congratulate him at their house. But Rajeev comes to know about him and calls the police. In the ensuing mishap Charles runs away with one of the twins whom he leaves on the railway tracks.

Due to the reflex action when the twin in the hospital rolls on his side, the twin on the tracks also rolls on his side and as a result falls off the tracks and is saved from the oncoming train.

Police arrest Charles but he claims the kid died in a blast that Charles engineered. Charles is arrested and is sentenced to twenty-two years in prison. Charles vows revenge against Rajeev, through his Mama (Manoj Joshi). The police advise Malhotra to take his wife and Prem and leave India.

Rajeev Malhotra shifts to London with Ankita and his son Prem (Varun Dhawan) for safety reasons, whereas the other twin is found by a woman named Kashibai and she raises him as her son in Mumbai, and names him Raja (Varun Dhawan).

Prem has grown up to be a kind and gentle Christian boy who aspires to be a musician. He is thrashed and bullied by an upperclassman, Rocky (Vikas Verma), on his first day of college and is pitied by Samaira. Samaira (Taapsee Pannu) becomes his only friend. Samaira is impressed by Prem's musical talents and asks him to come to her house and teach her music. Rocky warns Prem that Samaira is off limits as she belongs to him.

At the same time, Raja has grown up to be a fun-loving young man and staunch devotee of Ganpati Bappa, growing alongside his friend Nandu in the slums. Raja beats up a mafia's son Alex (Vivan Bhatena) at a Bappa ceremony, when Alex harasses Raja's son Nandu. Raja is advised to leave the country. He enlists help of Pappu Passport (Johnny Lever) to escape to London. Pappu also gives the contact of his friend Sharafat Ali, who will get Raja and Nandu a job and a place to live as well.

Raja meets Alishka Bakshi (Jacqueline Fernandez) on the plane and falls in love with her. Officer Dhillon (Pavan Malhotra) is after Raja as he is an illegal immigrant in UK. Raja and Nandu get a job as Pizza delivery boys at Sharafat's restaurant. When Dhillon questions Alishka, she learns that Raja is an illegal immigrant. Raja manages to escape every time he is caught, by telling a sob story of his family back home.

Now that Raja and Prem are both in London and are in close proximity to each other, their reflexes start operating simultaneously, and this creates a lot of confusion for the both of them and their girlfriends. They are also mistaken for each other by many people in the city.

Meanwhile Prem and Samaira are friends, but Samaira's mom Manmeet (Upasana Singh) is after her to ensnare Prem in her love. Raja kisses Alishka, and by reflex Prem kisses Samaira. Raja starts dating Alishka and Prem begins dating Samaira.

Now Prem's dad Rajeev takes him meet his childhood friend Balraj (Anupam Kher) to meet his daughter who is Alishka. Alishka is all over Prem (Thinking he is Raja), but Prem runs away from her. Officer Dhillon mistakes Prem for Raja and is now after him.

Samaira runs into Raja (thinking he is Prem), who defends her from goons and ends up winning her heart. Again, in a case of mistaken identity, Raja fights the bullies of Prem's college and ends up again impressing the heck out of Samaira.

Now Rajeev gets a call from Charles who is about to be released from jail. Charles vows to destroy Rajeev and his family. Rajeev has an accident and is rescued by Raja. in the hospital, Raja runs into Alex, whom he had beaten in Mumbai. Turns out he is Charles's son and has lost his memory.

Prem selects a ring for Samaira, but then Raja's friends Nandu (Rajpal Yadav) & Sharafat Bhai (Manoj Pahwa) come into the store and Prem (of course) refuses to recognize them. They are hurt. Prem and Samaira leave and then Raja & Alishka come into the jewelry store. The store owner mistakes Raja for Prem and gives Samaira's ring to Alishka, who is ecstatic.

Balraj calls Rajeev to congratulate him on Prem and Alishka's engagement. But Prem refuses giving the ring to Alishka. Samaira hears the conversation and breaks up with Prem. Now, finally, Prem and Raja run into each other and figure out the confusion. They do not realize that they are twins and conclude that they only share the same face.

Raja asks Prem to meet Alishka as Raja, and to get her back. while Prem asks Raja to meet Samaira as Prem to win her back. In the confusion, finally the girls figure out that Raja and Prem are twins.

Alex regains his memory and bring Raja and Nandu to Charles, who is Alex's dad. Charles holds Nandu hostage demanding Rajeev in exchange. Raja finally discovers that he and Prem are twins. Prem, disguised as Raja, brings Rajeev to Charles.

Raja arrives and beats up all of his goons. Alex's uncle locks himself with Raja. But soon, Raja's reflexes reciprocate helping Prem beat Alex. Raja and Prem find their father tied to a bomb and later deactivate it after Raja's fluke.

The Malhotra family is finally reunited, and Prem marries Samaira while Raja marries Alishka. They check out Raja and Prem outside who dance with them.