Lovecraft's work looks like it comes out of nowhere, until you read this book. Then Lovecraft's work looks like it comes out of The House on the Borderland and The House on the Borderland looks like it comes out of nowhere.
Lovecraft took from this book, such things as cosmic horrors, old Gods, found manuscripts, the first person narrator who is oddly unconcerned until it is too late. Even his writing style comes from that book. In fact the book feels very much like a combination of Lovecraft and the Stargate sequence from 2001. He is not quite as good as Lovecraft at his best and his writing is more still and more slowly paced. It is still a first rate horror/weird fiction book. Anyone, interested in Lovecraft should read it.
Very well done and worth reading.