This is a pretty interesting variant on the usual "heroic Investigators versus the great unknown" theme of most CoC campaigns (or Tail of Cthulhu campaigns for that matter). While most of the stuff published for Trail thus far has been the dark and depressing kind (which, while it's true to the spirit of most of HPL's works is nonetheless...well...dark and depressing), and this one is too, this one at least provides a structure and REASON why the players are acting that way. Not because of their inherently nihilist state of mind, but rather because they need to make a quick buck (or pound, in this case) in order to put bread and milk in the icebox. The investigators can be one of several types of "bookhounds" which are specialty occupations (with their own advantages and disadvantages) in search of those rare tomes and volumes so desperately sought after by evil wizards and "Dudley Do-Rights" alike, with the added incentive of being able to discover nefarious plots and decide what to do about them. The characters are gritty, no better than they have to be, and just as likely to commit a crime in order to accomplish their goal as not. Sort of like Kolchak: the Night Stalker in that sense -- balancing on that thin gray area between the legal and the downright illegal, and frequently crossing from one side to the other as the adventures go on.
The book provides a campaign setting based in post-Great War London, though it would be relatively easy to transpose it to any major western city (such as New York or even LA for that noir effect) or time. The rules are complete (though you DO need Trail of Cthulhu to understand the mechanics of the game system), and provide plenty of ideas and concepts to allow you to run your players through this type of campaign. While as I noted above pretty much all of the stuff published for Trail to date have been darkly themed, and this one isn't that much different, it feels more pulpish than the others and, as noted, could easily be transformed into something a little less "futile" in terms of long-term outcome. Really the premise of the campaign setting is absolutely brilliant -- where else can you come up with a valid reason for allowing the players to get their hands on something truly awesome in terms of forbidden lore without having them actually confront Great Cthulhu in the process? Plus, given that the business they are in is SELLING BOOKS, you can just as easily take it away from them ("What, that old leather-covered Manuscript with the cramped lettering by Olaus somethingorother, and the worm damage?" the aged proprietor responded to my urgent question; "I sold that to a gentleman that came in last week. Got a tidy sum for it too. You really need to see if you can find another copy!")
All in all, Kenneth Hite continues to demonstrate why he is one of the best horror and fantasy authors writing today. This supplement is a must-own for any Keeper looking for a new hook to get his campaign off the ground. As always it is well written, succinct (which might just be another way of saying "well written"), with plenty of great ideas and plot seeds for the alert GM to follow. I strongly recommend this volume to everyone!