Talk about minimalist writing. This book is written in the best hard-as-nails, noir style. And for that reason alone it's engaging. You can't quite tell whether you should like the protagonist too much, much the same way Lawrence Block's Matthew Scudder is an enigmatic protagonist. (Goodness, don't they get bored going to bars and sitting in their rooms, smoking?)
I did figure out the denouement early on. It's very hard to write mysteries without giving away the bad guy (who seems to be a good guy), so that's not a negative assessment.
The real eyebrow raiser is the ending. I will give nothing away, except to say that I believe I've never read another ending like it.