Before Alfred Hitchock, a shower curtain was just a shower curtain, and by that logic, taking a shower wasn’t something to be afraid of. But in 1960, the master of suspense turned an inanimate, everyday object into something forever associated with terror. Psycho hasn’t lost its power, even as five decades’ worth of horror has evolved into levels of extremity that have recently culminated in The Human Centipede II. If you haven’t seen it, and you appreciate anything that you can watch on a screen, you owe it to yourself to spend some time with Anthony Perkins’ creepy portrayal of Norman Bates, a lonely hotel manager who has a very strange relationship with his mother. When a beautiful woman on the run (Janet Leigh) seeks refuge at the Bates Motel … you can probably figure out the next step, even if you haven’t seen the film. The point is that from here springs most conventional horror-film tropes, and it holds up over time.