Nitin Bankar (Akshay Kumar) is a personal butler, cook, driver, watchman, gardener to a wealthy female industrialist (Archana Puran Singh) in Singapore. Like any young man, Nitin too, dreams of a better life, but misfortune is his constant companion and his reality is his job under Archana. He desperately wants to become rich and marry the love of his life, Anjali Kakkad (Katrina Kaif), who supports him financially.
Ram Mishra (Suneil Shetty), Nitin's best friend also came to Singapore with the dream of striking it rich, but ended up a courier delivery man. He falls for Manpreet Oberoi (Sameera Reddy), but her high society parents will never approve of marriage, not unless Ram has lots and lots of money.
In the midst of all this, is Harbans Chadda (Paresh Rawal), a shrewd businessman, is looking for ways to multiply his income and avoid his debtors. He decides the best way would be to marry his son off to a girl whose parents can give him a large dowry. He is introduced to Manpreet's parents at a Diwali function and is impressed by their social status. He introduces himself as a well-established businessman, impresses them and they decide to get Manpreet and Harbans' son (Chunky Pandey) married.
With several factors working against them, Nitin and Ram soon reach a dead end in their relationships. When both receive ultimatums from their girlfriends, they realize that only a life of vice can help them out of their misery. They come up with an audacious plan to kidnap someone important and demand a ransom. The kidnapping goes well, and both hide out at a local hotel while waiting for the ransom money. But misfortune is never far, and the kidnapping spirals out of control.
Meanwhile, Manpreet's wedding reception is being held at the same hotel that Nitin and Ram are hiding in. Soon, they are joined by a motley set of characters including a Chinese Don, a hired assassin, a ACB police inspector, a club dancer, an ambassador, a young frustrated double crossing wife, a letch, a drunken waiter, and a dead body nobody wants check into the hotel....
What happens next is De Dana Dan...full of many twists and turns that will leave you giddy with laughter...De Dana Dan...full of Masti and Madness!!!