Sameer (Salman Khan) is an ill-tempered person with terrible anger management issues ever since his parents died in his childhood. After he beats up a group of goons who tried to assault his girlfriend Roma (Amrita Arora), she breaks up with him due to his temper. Thus, as per his horoscope, he is very unlucky in love. With a heavy heart and in order to get away from everything, he leaves for Goa to take up a job as a lifeguard.
On the train to Goa, Sameer meets Suraj Prakash (Satish Shah), who lures Sameer into believing that he could be a thief by asking him where he kept the more important things, such as money, in his luggage. Sameer ends up staying awake the whole night to avoid being robbed while Suraj Prakash sleeps peacefully the whole night, having conned Sameer into guarding his own luggage. This is also something he admits to Sameer the next morning at the station in full overconfidence. Sameer later finds out that the former is a security guard at the very resort he is working in and retaliates by putting Suraj Prakash on guard duty for night times for 3 months, with the threat that he would lose his job if he ever slept even a wink on night duty. This causes Suraj a lot of trouble since he has never done night duty before and instead devotes night times to spending quality time with his wife. Having had a taste of his own medicine, he tries to desperately apologise to Sameer, later even with the help of his wife, but Sameer does not relent.
In Goa, Sameer meets Rani (Priyanka Chopra), an up-and-coming fashion designer and instantly falls in love with her. After many attempts at befriending her and a rough start with her father, (Amrish Puri), a former colonel in the military, Rani and Sameer become friends. However, Sameer’s ill-fated luck comes into play as he still has some rough incidents with her father and Rani, too gets angry with him since she overhears him saying bad things about her to Pandit ji (Raajpal Yadav).
Further trouble arrives in the form of Sunny (Akshay Kumar), who moves into the same house as Sameer and shares a room with him. He too meets Rani, falls in love with her and decides to cause further trouble by getting closer to her through the mistakes Sameer makes. This causes a lot of trouble between the two. It is evident that Sunny is out to ruin Sameer’s relationship with Rani so that he can steal Rani away from him. Sameer helps Rani with money that she urgently needs for a fashion show, but makes the mistake of calling himself her “well-wisher” while doing so. Rani wins the fashion show and while being felicitated for her victory, makes an open offer to her “well-wisher” to meet her so that she can thank him in person. Sameer, who had selflessly given Rani the money which he was supposed to pay for both his grandmother’s eye surgery and his sister’s wedding, goes to meet her but Sunny gets there first and claims to be the well-wisher and takes her away with him. Sameer follows on his motorcycle and ends up injuring the colonel severely. Sunny goes to the extent of taking credit for a painting of Rani that Sameer made. He kidnaps Rani’s dog, Tommy and frames Sameer. Sameer buys an identical dog from a pet shop and goes to the colonel, claiming that he has found Tommy. His ruse is later discovered by the colonel when the dog bites him and runs away.