He made an onscreen cameo in the 1937 film "Hollywood Hotel". Perc was the make-up artist for Bette Davis during the filming of "The Private Lives of Elizabeth and Essex" in 1939, where she became the first Hollywood actress to appear bald on screen (although it was actually only a couple of inches of her hairline which was shaved, to appear bald under wigs). This wasn't due to Westmore's ideas, but because Davis wanted to appear historically accurate as Queen Elizabeth. He very nearly changed Lauren Bacall's styling to something similar to Marlene Dietrich when Bacall attended for her screen test prior to her first film for Warner Bros. Bacall panicked at the suggestion and called producer Howard Hawks who insisted to Perc that he should leave her the way she was.