No one likes spoilers, right? But in some films a major plot twist comes so early that the choice is to either mention it or write an entire review consisting of little more than winks and nods. For example, in Nobuhiko Obayashi's "Exchange Students" ("Tenkosei," 1982) a teenage boy and girl — spoiler alert! — exchange bodies soon after the opening credits. Sorry if I've ruined it for you.