American MP Joe Washington and Australian Rose McAlister are swept back together when she returns to join Central Bureau, General MacArthur’s code-breaking group of eccentrics. Brisbane’s Bletchley Park.
Again and again, Joe is drawn to the Brisbane River. A man may have jumped into the river, a code breaker allegedly drowned by suicide, and an arm with an unrecognisable tattoo is pulled from the river at the submarine base.
With Rose’s help Joe follows the clues but he is quickly drawn into another confrontation with Frank Bischof and the Queensland Police.