I've had trouble with this author in the past (at least with the novels re-released through the American Mystery Classics line) - including DNFs and 1 stars - so this was beyond a pleasant surprise.
I couldn't resist the premise - a series of bizarre murders in Old Chicago, per the subtitle - and I'm glad I gave it a shot, because it's pretty darn good. The murders happen in fairly quick succession, and the detecting starts not long after the third one. We follow a few different sets of characters, who are pursuing various avenues on the various cases - but almost everyone agrees that it's likely that all of the murders were committed by the same person. But why? The victims don't appear to have anything in common, and while they were killed in the same manner, they were rather grotesquely displayed, and the displays didn't really have anything in common, beyond being displays.
The main amatuer detective, Walter Ghost, is a bit of a gasbag, but he's the first one to suspect who the killer is, and goes off in search of a motive. What he finds does indeed tie everything together; if I had read this book in one sitting, I would've cottoned on the culprit myself faster than I did - but I did guess correctly, which is always a plus :) The motive makes sense, but carrying a grudge for twenty years is certainly a choice. Not that I blame him, really.
The ending is also extra good, as the characters almost become aware of being in a novel, and the final sentence is *chef's kiss* I've never seen the words "The End" so perfectly positioned before, LOL.
Even if you haven't liked previous works by this author, if this premise interests you, give this one a shot. The pace moves along pretty nicely, and we aren't stuck in one character's head the entire time. The little clues sprinkled throughout come together nicely in the end, and aren't super-obvious "I AM A CLUE" while you're reading it.