THE INCREDIBLE SHRINKING MAN (1957)
JACK ARNOLD
Plot
Scott is contaminated by an unidentified spray and later by an insecticide, the consequence being that he starts to shrink. At first he rages at his loss of potency, but soon this turns to fear as he grapples with a domestic cat and, later, a spider in the surreal world of the cellar floor where he has been accidentally locked. Generally considered THE classic 50s B-movie and one of the best sci-fi movies ever made.