So, the bad guys have broken through the bank vault, stolen all the cash, and are heading towards the elevator intending their escape. The protagonist is nowhere to be seen... until the elevator opens and the bad guys see their stolen TNT right in the middle. Their jaws drop, and the timer counts down, 3, 2, 1...
This kind of surprise encounter with explosives can be used in all sorts of ways. [...] [tvtropes.org]