Code breakers : inside the shadow world of signals intelligence in Australia's two Bletchley parks

At the height of World War II in the Pacific, two secret organisations existed in Australia to break the Japanese military codes.

They were peopled by brilliant and idiosyncratic cryptographers with achievements in mathematics and the classics.

These men patiently and carefully deciphered the Japanese signals, ultimately making a significant contribution to the victories at Midway, Coral Sea and Milne Bay. But this is more than a story of codes. It is an extraordinary exploration of a unique group of men and their intense personal rivalries.

It is also the story of a fierce inter-national and inter-service political battle for control of war-changing intelligence between a group of Australian cryptographers with strong connections to British Naval Intelligence and a counter group allied to the US military.

What happened between these two groups would have consequences for intelligence services in the years to follow. Code Breakers brings this surprising and very secret world and the men who operated in it to rich life for the first time.