Because it's assumed they're fundamentally supposed to be about making you laugh, you generally expect comedy movies to bring some sense of happiness to your day. There's no sense in seeing a comedy if all it's going to do is bring you down - with climate change, economic chaos and massive inequality dragging the world to the edge of collapse, things are already depressing enough. It can be pretty distressing, then, when you get to the cinema only to find that that film that looked nice and amusing in the trailers is in actual fact rather gloomy. That's what you'd call a 'botched advertising campaign', and they happen all the time; for instance, just because it seems like a good way to get the punters in, a fairly downbeat film with one or two humorous moments might be sold by the marketing team as a straight comedy. It's a risky tactic, and one that often leads to audience disappointment and a feeling they've been tricked. Worse when it's a particularly depressing film is the feeling that you've just paid money to be both deceived and despondent. In this century alone, there have been a number of cases of films selling themselves as comedies when really the truth was much more complicated, and much, much darker. Here are ten of the finest examples.