A lowly pencil pusher working for MI7, Johnny English is suddenly promoted to super spy after Agent One is assassinated and every other agent is blown up at his funeral. When a billionaire entrepreneur sponsors the exhibition of the Crown Jewels—and the valuable gems disappear on the opening night and on English's watch—the newly-designated agent must jump into action to find the thief and recover the missing gems.

Footage from the game show "Who Wants to Be a Millionaire" is examined to reveal how a contestant almost cheated his way to the jackpot.