How are you supposed to follow up on one of the more deliriously fun films of the last few years? For Rian Johnson, whose initial foray into the whodunit genre was the delicious "Knives Out," the problem isn t merely to come up with a sequel that matches the original s playful intrigue and high energy, but to do it in a way that conjures up a new murder mystery that will keep everyone guessing, precisely when everyone is waiting for it and ready to pounce the second Johnson shows his hand (it is a very similar conundrum to what befell M. Night Shyamalan, when his twist-ending shtick got repeatedly exposed).