Having read #1, I read #4, going out of order because this was the one that won awards in the US. It turns out to be a sort of sequel to #1 as well, which is too bad because it repeats one of the most tiresome things in #1: the nymphomaniac victim. Nonetheless the dry-as-dust account of the investigation is really good fun, and there's a marvelously unmotivated grinchy passage about Christmas consumerism. Jury's still out on whether it's a social-democratic detective series or not.