It's a bit off-putting when the first sentence misses out two quite vital words, but persevere and it improves considerably; the content is worth it. For this work tells the story of a vast hidden store of arcane and esoteric knowledge... a character with an interest in such matters may have heard rumours of it, they may even have acquired the password to gain entry - or think that they do, it is changed frequently so they may be out of date!
We meet its owner, and his full stats are presented should the party meet him. There's also quite a bit about what is in the library and why Von Anstee accumulated it, which could prove interesting if only you can get in.
Then there's some other useful stuff. Characters who like books and finding things out might like to try one of the new occupations: book buyer, collector, researcher or tome thief. Even if you don't fancy these occupations yourself, their skills might make them useful hirelings when you are after a particular volume or piece of knowledge. There are some useful feats for people interested in scholarly research (although Speed Read is quite a good one if you are a reviewer too!). There are a few new monsters/creatures as well, suited to the mountains where the library is situated. (No precise location is given, think one of the more mountainous and wooded areas of the United States, the sort of place you might visit a national park or go hunting in.)
Finally. just in case the mere thought of a vast store of knowledge doesn't get you headed in the right direction, there are a couple of adventure ideas to start the action rolling.
A nice useful adjunct to a game where knowledge can be vital.... and once that could, with a few rule mechanical amendments, be used in any game system where knowledge can be the route to power, or to survival.