The Rian Johnson I heard about, the youthful genre wizard with a knack for inventiveness, never showed up for “Looper” or even “Brick,” which always seemed more like book reports about stories told better by other people. And he was conspicuously absent from “The Last Jedi,” which, let’s face it, was terrible. In fact it’s hard to believe that the same Rian Johnson who wrote and directed that self-satisfied bit of overripe fan fiction is also responsible for “Knives Out.” Because this is an unremittingly entertaining romp, a whodunit done with tremendous flair. At last he’s found a showcase that highlights his powers. This is the Rian Johnson that I want to see more from.