'Bookhounds' is a fine addition to the Cthuhlu Mythos and really plays to my sensibilities of what a Cthuhlu game is all about - the price of knowledge. This supplement offers your characters the opportunity to track down rare books of forbidden knowledge (for a variety of reason) through estates, auctions and even word-of-mouth in 1930's London. the new Occupations and Skills are well-matched to the setting, and the new rules on creating Bookshops are a lot of fun (in terms of making a Keeper and the players seriously think about the tone of the campaign). Whilst the Occupations are clearly designed to be integrated as a party, there are enough subtle differences to ensure the party cohesion will be tested from time to time.
The sections on the Book Trade, running a Book Hounds campaign and the sample module are all well-written, thoroughly engrossing sections that offer more inspiration than a rational (?) Keeper could realistically achieve. It sets out very clearly that there are a number of themes that can be explored and no two 'Bookhounds' games need be the same.
Likewise, the Monsters section is focused and useful - I can see plenty of opportunities for any of these to insinuate themselves into the game in a meaningful way. The last chapters of the book have a slew of maps, floorplans and reading lists - all of inestimable value to an enterprising Keeper.
In all, the book wieghs in at 185 pages, but the skill of the authors means that there is a lot more information in here than you'd think. The writing is very focused, but incredibly engaging and the general themes of the game are explored in a thought-provoking manner. I'd recommend this for any game that uses exploration of the unknown, such as Dark Conspiracy, Mage or even Nephilim. There are simply too many ideas to pass up. If you'd like to play in a 1930's 'Cthuhlu meets Warehouse 13' game, then buy it now.
[4 of 5 Stars!]