 Ops ( B ) was a deception planning department within the Supreme Headquarters Allied Expeditionary Force ( SHAEF ) during the Second World War . Established in the United Kingdom in April 1943 , the section was in charge of operational deception planning for the Western Front . Their major contribution was to Operations Cockade and Bodyguard , the latter being the cover plan for their Allied invasion of Normandy in 1944 . 
