For most of the past week, I ploughed through a W. Somerset Maugham collection with that signature pleasure one has in reading one short story after another. Maugham’s stories can wear thin after a while, however, owing to their formulaic structure. So I took a break for something completely different: The Ice House is a crime novel, but Minette Walters plays with a lot of crime conventions. It’s not entirely clear if a crime has…