Admirers of "The Father," Florian Zeller's shattering 2020 drama about dementia and filial devotion, will no doubt be intrigued to learn that Zeller has made "The Son," a movie that shares some (literal) DNA with its predecessor, but none of the first film's subtlety, visual elegance or thematic heft. Mawkish, obvious and manipulative, "The Son" is, quite simply, a disappointment, from its pat setup to its equally false - and, quite frankly, cruel - resolution.