The only male child in the family that sired six daughters, Prem has empathy towards the fair sex and decides to assist males to woo women so much so that he becomes popular as the 'Love Guru'. Amongst the men he assists are Bhaskar Chaudhry and Neil Bakshi. Klutz-like Bhaskar has fallen head over heels with his boss, a model and heiress, Priya Jaisingh. A disbelieving Prem refuses to assist him, but subsequently relents. Bhaskar uses his own charm to woo Priya successfully, and is introduced to her dad, Raj. Prem himself falls in love with a widowed single mother, Naina Shahani, a Journalist. Both men are satisfied with her respective lives not knowing that a scandalous secret will surface in the media - changing their lives forever.

Using their wits, Ganpatrao "Babubhai" Apte, Ghanshyam "Shyam", and Raju find themselves wealthy beyond their imagination. They each have a car, a palatial house with a huge swimming pool, that Babubhai is yet to familiarize himself with, and a very easy life. Then Raju finds out that he can double his wealth in 21 days, and meets with an attractive young woman named Anuradha from an agency in Bombay's business district. She informs him that the minimum investment is one Crore, and Raju quickly agrees to invest this money. He dupes another man by the name of Pappu into parting with 50 Lakhs, and the rest of the money comes through by getting Shyam and Babu to sign away their respective investments. After 21 days when the trio go to collect their doubled wealth, they find that Anuradha and her company have disappeared. Devastated, they move out of their bungalow and are now living in a shanty room in a Chawl when they get a visit from Pappu...

Originally from India, Tamil-speaking Shekar Subramaniam lives a middle-classed life abroad along with his wife, Sonia, and a school-going son, Prateek. While Sonia is busy writing a book on converting all female-related expletives to male, her husband is employed with Barron Industries, where the owner insists his staff come up with a plan to launch the ultimate video game or else he will change his organization to a restaurant and hire them as waiters. Hoping to create a super-hero, Shekhar instead faces criticism from Prateek - who hopes to instead see a kick-ass villain. This conversation does change Shekhar's thinking and he sets about to create an indestructible villain, calls him Ra.one (pronounced as in Lankeshwar Ravan) and its arch-enemy G.One (Jeevan). Prateek will have to regret passing on this idea on to his father - for soon their lives will be shattered when the shape-shifting Ra.One will find a way to enter the real world...