World War II/Double Cross System

The Double Cross System or 'XX' System, was a wartime expedient of the British military intelligence arm, MI5?, which involved turning captured Nazi agents and using them to broadcast mainly erroneous information to the Nazi high command.

Often the turned agents were given factual collateral with which to build up their reputations. One of the major players in the Double Cross System was /Garbo, who built up a highly fictitious network of agents, and became respected by the Abwehr to the extent that they stopped landing agents in Britain after 1942, and became wholly on the spurious information which was fed to them by /Garbo's network.

This misinformation was critical to the success of D-Day.