The show: Big Brother, 2004

The shock: Instead of sitting down with host Gretel Killeen and talking s--- for half an hour, Big Brother evictee Merlin Luck taped his mouth and held up a sign (which he'd secretly smuggled into the house) advocating for refugees. Gretel, producers, the show's psychologists and even Merlin's dad all tried to convince him to speak, but no dice. Gretel, while clearly ticked off, handled the live-TV debacle pretty well.