The Incredible Shrinking Man

The Incredible Shrinking Man is a 1957 American science fiction film directed by Jack Arnold, based on Richard Matheson's 1956 novel, The Shrinking Man. The film stars Grant Williams as Scott and Randy Stuart as Scott's wife, Louise. While relaxing on a boat, Scott is enveloped by a strange fog. Months later, he discovers that he appears to be shrinking. By the time Scott has reached the height of a small boy, his condition becomes known to the public. When he learns there is no cure for his condition, he lashes out at his wife. As Scott shrinks to the point where he can fit into a dollhouse, he has a battle with his family cat, leaving him lost and alone in his basement, where he is now smaller than the average insect.

Synopsis from Wikipedia, CC BY-SA 4.0. Everything below written here.

Poster by Reynold Brown (Public domain).