In an early scene from Mantra, a little girl at a shop counter asks for King Chips. All around her there lie only packets of the upstart brand Kipper, which the shopkeeper is hardselling. She is undeterred. King Chips is what she wants and King Chips is all she will have. The dukaandaar finally gives in, fetching a packet from a corner at the back of his establishment where he had stashed it away from the gaze of customers, not having bargained for this one insistent child.

Kapil Kapoor (Rajat Kapoor) is going through bankruptcy for his business of Kings Chips post liberalization. New players are in the market and Kipper Chips is killing KK's business. His son, Viraj Kapoor (Shiv Pandit) has chosen to have his own business, which is a chain of restaurants named Mantra, with his sister Piya (Kalki Koechlin) as the chef. KK's wife, Minakshi (Lushin Dubey) is depressed and unhappy with the way their relation is heading and is contemplating divorce.

It's the year 2004 and India is shining like the sun as far as the economy is concerned, yet all is not well with Kapil Kapoor, the Delhi-based proprietor of King Chips. The multinationals are buying out the market as he fights, what seems like a losing battle, to save his company. But that's just the professional front. His personal life, too, is in a mess. While his eldest son Viraj (Shiv Pandit) is pursuing his own restaurant business, his younger daughter Pia (Kalki Koechlin) is desperately looking to break out and live on her own.

The year is 2004. A wealthy businessman who lives in Delhi with this family - well-preserved wife, three children - is facing bankruptcy. In some quarters in the Capital of India, the fruits of economic liberalization are being gobbled up; in others, they are pure poison: Mantra is about these people, their rocky lives, and that time.