Biggles Foreign Legionnaire has Biggles and Ginger joining the French Foreign Legion to try an infiltrate a worldwide conspiracy ring deliberately fueling conflicts to allow profitmaking from gun-running and other supplies.

Following a tip-off from Marcel Brissac, Biggles and Ginger join up (joining a very well behaved legion) and, because of their flying skills, are soon in the thick of it. After surviving being shot at by French security guards (serves them right for trying to steal a plane) they end up holed up in a ruined castle in Iraq defending themselves from a Kurd attack, supported by no other than Erich Von Stalhein. As Biggle's says: "War makes strange bedfellows".

Biggles and Von Stalhein fighting side by side is pretty amazing stuff, particularly to Colonel Raymond who flies in to pick them both up. That plus Biggle's desparate search for cigarettes. As soon as Von Stalhein arrives, all he wants off him is a ciggie.