It has been at least forty years since I've seen this film, and the memory of it still haunts me. Perhaps it was because of my (at that time) tender age, but this short gave me a full blown case of the Whim Whams. Jasper needs to go see a dentist but is frightened to do so. In a dream sequence he visits a dentist's office run by Professor Scarecrow. The Professor begins his treatment, and Jasper finds himself strapped to the chair and facing the relentless approach of a horrifying machine. From there the terror and tension builds to a climax which Pal would not match (in my opinion) until WAR OF THE WORLDS some years later.