Preview by Frank Belknap Long is a science fiction short story written in the mid-20th century. It centers on a film preview that turns into an alien intrusion, exploring how perception can be hijacked and how memory and culture can be stripped away by watchers beyond Earth. At a private screening, the smooth-talking Mr. Scanlon promises critics a new, brutally realistic experience and showcases Stella, a “stripped” actress. A grand Western unspools, then ruptures: a tentacled being rides into the Black Hills, the landscape mutates, Stella grotesquely transforms, and Scanlon abruptly vanishes. The tale closes with a chilling coda: a week later saucer-folk arrive in force and erase from human minds the treasured knowledge of Earth’s wonders, ensuring that no one remembers the preview—or understands why it happened. (This is an automatically generated summary.)