The Devil-Doll (1936) on Netflix

Plot summary

Paul Lavond was a respected Paris banker until he was convicted of robbing his own bank and killing a night watchman, and sent to Devil's Island. He serves more than seventeen years, then escapes with Marcel, a fellow prisoner who has been working on a formula that reduces people to a sixth of their size, meant to stretch the planet's resources. Marcel dies soon after. Lavond joins his widow, Malita, and turns the formula toward the three associates who framed him and took his business while his family was left in shame and poverty. Disguised as Madame Mandilip, a seller of lifelike dolls, he returns to Paris to settle the account.