Write a scene in which an army of cats descends on London, and most people will assume that at any moment they’ll lose interest and start rolling around in a sunbeam or chasing laser pointers. Kitties are just too cute and fluffy to be scary, and scenes of their soft paws poking under doors induce giggles rather than gasps. When a radio announcer is buried alive in an avalanche of mewling kittens, the immediate reaction is not one of horror but a soul-deep “awwwww…”