One of Alfred Hitchcock's most famous (and scariest) films, The Birds is rich with wit and subtlety as well as suspense thrills. One the one hand, it lampoons its characters, mocking their pettiness and, later, their helplessness. And on the other, it plays off our natural human fear of the unknown. That the film doesn't even attempt to explain the rationale behind the birds' aggression is to its credit.