Not every film can be good; in fact, most aren't. But it takes a special kind of failure to make someone just kiss his or her $10 goodbye and get up and leave.
We've all been there. Sitting in that darkened room, watching as something particularly ungodly unspools before our eyes. And somehow, bad turns to worse — and it gets so bad that you're willing to forfeit your hard-earned cash and just get up and leave. It doesn't happen often, but it happens.
It last happened to me while seeing the 2006 Michael Rapaport toadstool Special. This "adventure" about a normal guy who thought he had superpowers got dumber as it went on, and not in an interesting way, until it finally reached unbearable. Almost walked out of both The Happening and Knowing, but that kind of misbegotten apocalyptic insanity needed seeing through all the way to the end.
When was the last time it got so bad you simply couldn't take it anymore?