The game revolves around the opening of a set of numbered briefcases, each of which contains a different prize (cash or otherwise). The contents (i.e., the values) of all of the cases are known at the start of the game, but the specific location of any prize is unknown. The contestant claims (or is assigned) a case to begin the game. The case's value is not revealed until the conclusion of the game.
The contestant then begins choosing cases that are to be removed from play. The amount inside each chosen case is immediately revealed; by process of elimination, the amount revealed cannot be inside the case the contestant initially claimed (or was assigned). Throughout the game, after a predetermined number of cases have been opened, the banker offers the contestant an amount of money and/or prizes to quit the game, the offer based roughly on the amounts remaining in play and the contestant's demeanor, the bank tries to 'buy' the contestant's case for a lower price than what's inside the case. The player then answers the titular question, choosing:
- "Deal", accepting the offer presented and ending the game, or
- "No Deal", rejecting the offer and continuing the game.