In his history of the Special Operations Executive, he wrote that the Allied intelligence effort in the Netherlands had been penetrated from the start of the war. Two Secret Intelligence Service (SIS) agents, Captain Sigismund Payne Best and Major Richard Stevens, had been captured in November 1939 during the Venlo Incident. This culminated in the capture of some 50 British and Dutch agents by the and the in Operation North Pole. Flying with the RAF To fly for the RAF Roelfzema first had to qualify. Poor vision had disqualified him earlier from mandatory service in the Dutch reserves. The glasses he wore for visual correction should have disqualified him from pilot training as well. Ever resourceful, Roelfzema worked around this by smuggling in a lens and palming it during his vision test. He passed and was sent to Canada for flying school. He trained in single-seat fighter aircraft and was awarded the gold cufflinks on graduating his training course given to the best pilot cadet in the training group. On returning to England he found himself sidelined, unable to get posted to an operational squadron. An unlikely avenue was with the elite Pathfinder Force of Bomber Command's most experienced and best pilots, whose job it was to guide the Bomber stream of the RAF night bombers through all weathers to their targets in Germany. While lamenting his situation with girlfriend Midge Cooper at a public house, 'Hamish' Mahaddie happened by. Mahaddie was a wing commander with the Pathfinders, who frequented the public houses after giving talks on Pathfinder techniques to see if he could recruit any pilots for his force. "Here's just the man we need!" said Cooper. Though hesitant to take on an inexperienced pilot, Mahaddie granted Roelfzema a spot at RAF Warboys, where the group trained pilots on twin-engine aircraft and night flying in preparation to work in the PFF. To obtain a position in the squadron, Roelfzema needed to score an "above average" in the training course, which he did. Thus the near-sighted novice fighter pilot was posted to the elite PFF, flying the De Havilland Mosquito. Roelfzema flew with 139 Squadron. His aircraft was unarmed and relied on its speed to escape from German night fighters and luck to get through the flak. Normally Bomber Command crews were considered to complete a tour after 30 sorties. In the Pathfinder Force crews initially were required to complete