Not a lot of depth in The Thin Man - but a lot of surface

I don't read many mysteries or crime novels so who am I to weigh in but I did start Dashiell Hammett's "The Thin Man" last night, in the Library of America collection of his novels (read Maltese Falcon a few years back) - totally entertaining so far, in the way that very few novels, mystery, literary, or otherwise were then (1930 or so?) or now. It's not that we actually believe in the plot - a weird concoction of events, as a beautiful dame (of course) seeks out retired detective Nick Charles for help in finding her estranged father, and it turns out estranged mom looking for him, too, and then he's in the news as his mistress (maybe) is found shot dead, so why was everyone looking for him and who dunnit? The beauty is that March finds himself in the middle of the case and, unlike all other detectives or protagonists in crime novels, he really has very little interest in the case and no motivation to help - he's above it all, independently wealthy having married Nora (March) and now managing her money: working hard so that I don't lose the money I married you for, as he memorably puts it. The whole novel is built on and driven by the terrific, sharp interplay between Nick and Nora, quips and cocktails - and writing is very funny, and subtle - not the sledgehammer tough-guy dialog that Hammett developed in Sam Spade or that Chandler developed for Marlow (or Parker for Spenser, et al.), and that's much more familiar to us in many detective series (and is notably absent from the very popular Scandinavian detective novels, more cerebral and morose) - they're really what used to be called "high society" types, and the beauty of the story is in watching them deal with the various thugs and criminals, and never losing their cool. It's obvious that Hammett drew on the tone and style of repartee that he must have engaged in all the time with Lillian Hellman. Anyway, not sure how much I'll have to say about the novel going along - there's not a whole lot of depth, though that's made up for by a lot of surface.