I‘m not a fan of “whodunit“ books and I suspect this is an even more plodding example than usual. In many places the author mistakes a list of facts/directions as plot. Written over years, it began as a series of anecdotes. There are too many ideas, none fleshed out properly. Despite this, it's not an entirely bad book. I did enjoy the 1940s NYC setting, the name dropping of the many artists, the multi-narrator structure, and the central mystery.