Sing or Swim

Contestants take the stage (in full costume) and stand over a trap door. Despite the title, they are allowed to sing, dance, tell jokes, etc. The audience, besides cheering or jeering, keys in rejection votes for the act. When the rejection vote breaks 50%, the trap door opens and multiple camera angles capture the priceless expressions of the startled contestants as they are ejected mid-note. Those that survive for two minutes go on to the next round.

Round 2

The show turns from hilarious to absurd as the survivors of round 1 participate in a free-for-all shoving match on the surface of a giant vat of cornstarch and water (the substance acts as both a solid and a liquid). The last contestant remaining on the surface is the winner (so to speak).

Alternative

The trap door remains, but the swimming pool is replaced with a water slide that dumps contestants out into a dirty back alley. The drawback is that I can't use my clever title.