It broke box-office records in 1975, and probably posted an aesthetic landmark, too—in proving that actors and characters were completely redundant in the shopping center cinema of the 70s. Steven Spielberg’s mechanical thriller is guaranteed to make you scream on schedule (John Williams’s score even has the audience reactions programmed into the melodies), particularly if your tolerance for weak motivation and other minor inconsistencies is high. It spawned a number of imitations (including Grizzly, Day of the Animals, and the unforgettable Worms), most of which failed. But the formula has lived on in the Alien series and most contemporary films with aspirations toward suspense.