Based on Norman Corwin's satirical radio play My Client Curley, Once Upon a Time is an engaging bit of whimsy, completely dominated by the personality of star Cary Grant. It all begins when fly-by-night Broadway producer Jerry Flynn (Grant) learns of a trained caterpillar (!) that dances to the tune of "Yes, Sir, That's My Baby." In short order, Jerry has promoted Curly the Caterpillar to international stardom-and in the process he alienates both Pinky Thompson (Ted Donaldson), the impressionable 9-year-old who owns Curley, and Pinky's attractive older sister Jeanne (Janet Blair). Eventually, Flynn comes to his senses and regains his essential decency-though it's too late to continue capitalizing on Curley, who has turned into a non-dancing butterfly! Full of delightful contemporary references and "cameo appearances" by such celebrities as producer Walt Disney and radio commentator Gabriel Heatter (both played by uncredited impressionists), Once Upon a Time proved an agreeable diversion for wartime audiences.
by Hal Erickson synopsis