THE EIGHTH CIRCLE (1958) by Stanley Ellin (1916-1986) is a semi-successful Amalgam of three forms of fiction: (1) a Fair-Play Puzzle, (2) a Male Heroic-Erotic Fantasy, and (3) a Character Reformation Tale. It's as though Ellin decided to dice up puzzle parts from Rex Stout's or Agatha Christie's mysteries, then dice up male fantasy parts from Ian Fleming's James Bond Thrillers ... and then sprinkle these parts on to a plot that's a close facsimile of the one Charles Dickens used in GREAT EXPECTATIONS.
The protagonist of THE EIGHTH CIRCLE is Murray Kirk, the head of a successful New York City detective agency. He is hired to help clear a policeman who has been accused of taking a bribe, but instead he wishes to find evidence proving that the policeman is guilty. Cynicism is part of the reason, but Kirk, who has been a womanizer into his mid-thirties, is smitten by the policeman's beautiful fiancée and wants her for himself ... and to accomplish that, he needs to break the couple up, an activity that is both unethical and unprofessional.
During his investigation, like James Bond, Murray Kirk is beaten up and taken to the secluded mansion of a type of super-villain ... and then (bruised and battered) he sets out on a daring and dangerous night raid to get revenge ... and evidence. And when the super-villain comes to deal with Kirk ... well, read for yourself to see who gets the better of whom.
Along the way, as evidence slowly accumulates, Kirk and we learn that some of his assumptions have been mistaken, and we readers are given a fair chance to piece things together for ourselves before Ellin or Kirk reveals the "solution." We're even given a chance to guess what Kirk will decide to do about his new material.
Minor SPOILER #1: Near the ending a plot hole appears: to help Kirk resolve some major problems he's having with people in high places, a convenient case of murder suddenly comes to light. The murder, sad to say, is "solved" by some sleight of hand: instead of Kirk or his colleagues producing any solid evidence of anyone's guilt, the guilty person happens to come into a room and confesses.
Minor SPOILERS #2 AND #3: Kirk, as readers will be genuinely delighted to see, ultimately "does the right thing" ethically and professionally. And shortly thereafter, like Pip in Dickens' GREAT EXPECTATIONS, Kirk is almost magically rewarded for being good.
A few other reviewers have criticized THE EIGHTH CIRCLE for being, among other things, often "pretentiously" written and often highly "implausible." I believe they are correct, with the latter fault being by far the more serious one. In my view, the two final scenes where Murray Kirk receives his "rewards" are the most preposterous in this novel, and the entire book would have been very greatly improved if they'd both been omitted.
Yes, most of us know that THE EIGHTH CIRCLE won the Edgar Allan Poe Award for best mystery of 1958. Perhaps that says something about the quality of other mysteries published that year. Or perhaps it says something about the tastes of the judges of that year. Considering its faults and its strengths, if I were giving this book a letter grade, in my judgment it deserves only a "C+".