The Circumference of the World basically centres around the search for a book that disappears once read, but the novel covers a lot of ground across a few main characters, a number of locations & time frames, and told in a combination of first and third person.

It's quite an ambitious novel and different to anything I've read of the author's previously; with big metaphysical concepts and the timelines as mentioned, from the 1920's to 10,000 light years away. It touches on theories like the Anthropic Principle, the Fine Tunes Universe theory and the Fecund Universes theory, weaving these scientific viewpoints into the story.

Much of the back half of the novel has a definite nod to the Golden Age of SF, with the author character interacting with people like Heinlein, Asimov, van Vogt, etc. which gives it a realistic feel.

Of note to me personally was that one of the main characters was born in Vanuatu, and the description of daily life was spot on - the author lived there for a year, and I lived there in my childhood for 4 years as well! The descriptions of the coconut trees, bush knifes, black and White Sea snakes, the smell of fires at night, kava, etc. all brought back strong memories.

If I was to pick a negative it would be that maybe it's a bit too ambitious, trying to fit all these concepts into a ~250 page story is challenging and some of it feels a bit rushed (the author himself described it a couple of years ago as "a big, messy, ambitious manuscript that I’ve been working on for a long time.") So it wouldn't be something I'd recommend to newcomers to the author, but it's a must read for those familiar, or up for a challenge.