Jacques Poirier was a Frenchman who joined Maurice Buckmaster's F section of the Special Operations Executive (S.O.E) in London. He was given the codename Nestor and parachuted into the R5 region that included the Dordogne in order to encourage and arm embryonic Resistance networks. Most French maquisards believed him to be English but when he first began his training he spoke very little English at all. He formed strong partnerships throughout the region and he became central to the operations in the region that preceded and followed D-Day in June 1944. His story is retold and the contribution of SOE agents analysed and assessed in Defying Vichy: Blood, Fear and French Resistance.
Poirier's story, told in his own book 'La girafe a un long cou' (a BBC coded message signifying the upcoming D-Day landings) and still available (with a bit of searching) in an English translation as 'The Giraffe has a long Neck' (Leo Cooper, 1995) is a brief but enthralling account of his exploits. However a full and detailed interview is also held at the archives of the Imperial War Museum, and has become available digitally in its entirety (follow the link below). The October 1988 interview is in English and well worth a listen.
This link leads to the archives of the Imperial War Museum, and to the page that houses all four reels of the interview https://www.iwm.org.uk/collections/item/object/80010224