 Meanwhile, after failing to find any position as an intelligence officer in the Middle East, Sykes returned to the UK in May 1943, volunteered for the Special Air Service (SAS), and was posted to the Commando Training Depot at Achnacarry Castle, Invernesshire on 1 July 1943.As an SAS officer, Sykes, who spoke fluent French but could not pass as a native, undertook extremely hazardous work with the French Resistance