Well, yet another book crossed off this io9 list of the "Top 10 Greatest Science Fiction Detective Novels Of All Time". And another one I pretty much hated while reading. It was nominated for a Nebula Award, which means that a lot of people liked it a lot better than I did. (Why do I keep reading books I hate? It's a rule I set for myself years ago, and I think I had a good reason for doing so, but … it may need revision.)
Anyway: this one is a 1994 effort by Jonathan Lethem. This was his very first novel, and (to be fair) he's gone on to become a serious critically-acclaimed writer of best-selling literary fiction and some non-fiction. Lethem's Wikipedia page quotes him as getting significant literary influence from Philip K. Dick, marijuana, and punk rock. That explains a lot.
The book is set in a dystopian future where artificial evolution has granted intelligence to kangaroos, apes, sheep, etc. Drug use is universal, a snortable substance called "make" is made available for free; citizens can customize the blend of chemicals to give you the desired outcome of addictiveness, forgetfulness, etc.)
The protagonist, and first-person narrator is Conrad Metcalf, a private "inquisitor", which is what detectives are called. In a seedy world, he's unusually seedy himself. He is hired by Orton Angwine, who believes he's being framed for the murder of Dr. Maynard Stanhunt. By coincidence—or is it—Metcalf had previously been hired by Stanhunt to follow his wife around.
The book attempts a Chandleresque hard-boiled style, where Metcalfe's narrative is full of colorful observations and wisecracks. This is not easy to do right, and… well, I'd rather have re-read Chandler for the fourth or fifth time, instead. This doesn't even read like a good Chandler parody; it's more like a parody of a bad Chandler parody.
Most of all, the book never provided me with a satisfactory answer to the question: Why should I care?