Scott Warden is an American software engineer. When his work contract in Thailand is cancelled he decides to stay on and live a carefree expatriate beachlife existence with his wife and young daughter, surviving on their savings. One night the temperatures drop considerably and Warden and another American ex-pat, Hitch Paley, travel into the Chumphon jungle evading the police roadblocks and discover the first Chronolith.

Standing their in the middle of tropical forest is a two hundred foot tall stone pillar partially encased in ice. This is but the first arrival of many all celebrating military victories of a general Kuin, this first inscribed with the date December 2041, a date a little over twenty years in Scott Warden's future.

Whilst this is going on his wife (soon to be ex-) leaves him and takes their seriously ill daughter back to the USA.

Following the second arrival in the city of Bangkok Scott joins a project lead by an old college tutor, Sue Chopra - a theoretical physicist trying to uncover the secret of the Chronoliths.

I was a little worried when I started to read this book. Since I had first heard the premise I had wanted to read this book. The idea had gripped me, and that added to the fact I've read and enjoyed previous books by Robert Charles Wilson meant I was expecting a lot form this.

It didn't disappoint, but neither did it follow the expected idea I had for the book. This is probably a good thing as it was very refreshing to read a book that surprised me. And this is why I don't want to include more here about the story itself. I do not want to spoil that aspect of it.

That said, it is very well written, the characters are well rounded. The sense of time passing and the effect of the Chronoliths becoming more apparant throughout society and nations is handled extremely well and without over-elaboration. This is simply a good sf story form concept to execution.