The spy ring that has always fascinated me, is the Lucy ring that supplied Stalin with top secret plans that sometimes hit his desk before German commanders received it.

Intelligence professionals and historians alike have long regarded the Red Orchestra as one of the most successful spy rings that operated during the Second World War.

The Red Orchestra spy ring consisted of three main branches: the network in France, Belgium, and Holland; the Berlin network; and a remarkable group of agents, known as the "Lucy Ring," that operated from the relative safety of neutral Switzerland. The Berlin-based Red Orchestra agents included Harro Schulze-Boysen, an intelligence officer assigned to the German Air Ministry, and Arvid von Harnack, an employee of the German Ministry of Economics. These men, as well as several others, reported extraordinarily sensitive information from key areas of the German bureaucracy in the German capital itself.

The Lucy Ring, perhaps the most important branch of the Red Orchestra, possessed some impeccable sources of information. These sources included Lieutenant General Fritz Theile, a senior officer in the Wehrmacht's communications branch, and Colonel Freiherr Rudolf von Gersdorff, who eventually became intelligence officer of Army Group Center on the eastern front. The Lucy Ring provided Soviet leader Josef Stalin with extraordinarily accurate information on Nazi intentions on operations on the German eastern front. The Germans apparently knew of the existence of a Soviet spy ring operating in fairly high levels of the Reich Government administration as early as 1941. However, like many counterespionage cases, it was only after two years of painstaking investigation that the case was finally broken.

Any clues to any other top Germans capable of passing that sort of info?