High and Low (1963) on Netflix

Plot summary

National Shoes is split between executives who want to make cheap, disposable footwear and those loyal to its sturdy, unfashionable line. Kingo Gondo, a manager and major shareholder, has secretly mortgaged his property to buy enough shares to take control of the company himself. On the eve of the deal, a caller claims to have kidnapped his son Jun and demands a ransom, a sum that would consume all the money he has borrowed. Jun is found at home, but his playmate Shin'ichi, the chauffeur's child, is missing; the kidnapper took the wrong boy and says the demand stands. Gondo must decide whether to save the child or carry out his plan.