Chandramohan Manohar Sharma, better known as Charlie (Shah Rukh Khan), is a street fighter who has been yearning for revenge from Charan Grover (Jackie Shroff) for 8 years. Grover, with his rich and despicable mind, labeled Charlie’s father, Manohar Sharma (Anupam Kher) as a thief because Charan had conned him into stealing his own Diamonds (he stole his own diamonds and framed Sharma for stealing them) priced at INR 100 crore ($15 million). Charlie finds out through the media that diamonds worth $300 crore will reach the Atlantis Hotel on Christmas Eve. He wants to steal the same diamonds and frame Grover. To accomplish this, he must assemble a dynamic team.
First in his team is Former Army Bomb Squad Captain Jagmohan Prakash, or Jag (Sonu Sood) who has a hearing deficiency which happened when he failed to defuse a bomb; he gets furious when someone insults his mother. Second on his team is Tehmton Irani, or Tammy, (Boman Irani) who is an overweight jogger and suffers from epileptic fits. It is also revealed that Tammy and Manohar were best friends. Third on the team is Rohan Singh (Vivaan Shah), a young hacker who Charlie believes can hack into Shalimar’s computerized system. He is also Jag’s nephew. After thoroughly researching about the vault, the team finds the main vault comprises a biometric lock (fingerprint lock). The problem is that only one person can access the vault at any time: Vicky Grover (Abhishek Bachchan), Charan’s son. So they enlist the aid of a lookalike, Nandu Bhide (Abhishek Bachchan). Charlie describe his team as ek full time bewda (Nandu), ek sanki jadeya (Tammy), ek bhari banduk sipahi (Jag), ek badmaash bachcha (Rohan).
The team heads to a warehouse which was originally their workshop for a rehearsal. It is revealed that Tammy was immensely in love with the Shalimar vault and he is the only one to open the vault without the combination. The real Shalimar vault has a laser shield in front of the vault whose code combination is changed everyday. The team finds out a weakness that the Shalimar safe is in the Altantis hotel underground which is connected through an air duct system which is further connected to room 9C, a lounge room in Atlantis. Charlie then explains a problem, being that room 9C is booked for a team participating in the World Dance Championship (WDC), a dancing competition. The group refuses, but Charlie re-motivates the group, convincing them to become a dance team.