British and American intelligence agencies discover that the Chinese are carrying out secret research with the North Koreans to develop new nuclear weapons. A daring and dangerous operation to capture the details is carefully planned by MI6 and eventually put into action with the help of the SAS when a disillusioned atomic research physicist refuses to defect. But the plans unravel, and a top British agent finds himself on his own in a hostile country, and in a desperate race against time. He eventually manages to secure the information from the North Korean scientist before he dies of cancer and before the American CIA can get their hands on it, only to find that his escape route has totally collapsed. His only option appears to be for him to escape across China, with their nuclear secrets in his back pocket, to find the only possible source of help left to him. He evades detection, capture and attempts on his life before finally reaching home, where tragedy eventually catches up with him in a moving and unexpected twist at the end of an intriguing spy thriller.