Allahabad stock trader Rizwan Ahmed (Rohan Vinod Mehra) arrives in Mumbai determined to work with his hero, Gujarati financial maven Shakun Kothari (Saif Ali Khan). Rizwan bluffs his way into the city's largest trading firm and manages to convince them to give him a job. He ropes in a high-profile client and with the help of his co-worker and girlfriend Priya (Radhika Apte), he begins a successful career at the firm. Basically Shakun wanted to buy a Pharma firm, but when the owner refuses to sell and insults Shakun. Shakun starts a rumor that a diabetic drug approval for the firm was rejected by the FDA. He bribed a minister to give credence to the rumor. The stock tanks 40 points the next day. Rizwan is under pressure to make a trade, and calls the owner of the Pharma firm who asks Rizwan to sell 14% shares at 200. Priya helps make the trade at 198. The buyer, unknown to Rizwan was Shakun. Shakun laughs as he had offered 250 to the owner in the beginning.Shakun Kothari is introduced as a ruthless corporate shark, who takes control of a company by ousting its chairman by threatening to reveal that his son is gay. Shakun was illiterate and used to smuggle diamonds. Slowly he won the trust of his boss and seduced his daughter to marry her. The boss gave him his 50 Crore business empire as dowry. Shakun became a player overnight and succeeded with his street smarts.MEanwhile SEBI is monitoring Shakun and has a file on him on his involvement with various stock manipulations. They also suspect that Shakun was the client for one the brokers (where Rizwan works) who committed suicide. But no evidence.When attending an event with Priya, Rizwan spots Shakun Kothari and gives stock advice that turns out to be correct. Kothari then hires him as his broker, warning that he can never lose him any money. After his first trade with Kothari's funds ends badly, Rizwan is desperate not to lose Kothari's account and illegally uses insider information from Priya to recoup Kothari's losses.Rizwan becomes close to Kothari and his wife Mandira (Chitrangada Singh), visiting Kothari's lavish home and relaxing on his yacht with Priya. Mandira gets attached to Rizwan and warns Kothari against ruining his life or breaking his trust. Meanwhile, Kothari offers Rizwan a chance to make even more money when he learns that the government is going to begin accepting bids from telecommunications companies for a new spectrum allocation project. Kothari informs Rizwan that he has bribed a government minister to select a company called Skycom (to issue fresh spectrum) and the two can make a killing on the deal if they can buy the company now. Kothari gives Rizwan the money to buy Skycom and Rizwan becomes the company's president & CEO. Under Rizwan Skycom lists on the share market and the price zooms.However, Skycom's bid is rejected, and Rizwan is ruined when Kothari sells off all of his Skycom shares right before the announcement of the bid winner. Rizwan discovers that Kothari deliberately set him up to take the fall for Skycom and that he arranged for Priya to influence him from the beginning. But Kothari doesn't tell Rizwan that Priya actually fell in love with him and wanted to come clean, before Kothari also silenced her with his plan of the Skycom deal. SEBI agents detain Rizwan for insider trading, but their real target is Kothari. Using information from Kothari's wife, Rizwan is able to prove that Kothari has been bribing government ministers with diamonds. SEBI raids the train thru which the diamonds were being couriered and find the diamonds in the lunch box of the driver. Priya deposes against Kothari in court and she doesn't want any more people to commit suicide because of her.