This is the small companion book to the exhibit of the same name. There is a larger, heavier, and costlier book. I saw the exhibit in Washington, DC at the National Geographic Museum.
This small companion book is a good remembrance of the show. You will not learn really anything more than the wonderful show tells you, but it does have lovely pictures. The show itself is worth going to, and includes some items that have never left Greece until the show. It does blend a bit of Hollywood in - for instance the 300 section is referring the movie, yet then the history is put front and center.