A horse walks into a bar.

This absolute classic of the bar joke genre operates on a few hilarious levels. The foundation (Review) is pure absurdity; the image of a horse trotting up to a bar is funny on its own. But the real magic is the wordplay at its heart. The common idiom for sadness, "a long face," also happens to be a perfect literal description of the animal's head. The bartender's question is both a concerned inquiry and a deadpan observation, creating a perfect, groan-inducing pun.

What makes this particular version so clever is the second punchline, which subverts the whole setup. Just when you're appreciating the simple pun, the horse (Review) gives a genuinely depressing reason for its mood. This unexpected dose of sad reality turns a silly joke into a tiny, tragic story. It's a masterclass in taking a well-known formula—the "animal walks into a bar" setup—and adding a twist that makes the listener laugh at the sudden, ridiculous pathos of it all.