IMAGINE IF HE'D BEEN HEALTHY?:

Considered a sickly child, Robert was sent to a succession of private schools for the jeunesse dorée in Switzerland and Austria where, in 1938, he was taken on a school trip to Berchtesgaden, Hitler's Alpine retreat. When Hitler's convoy drew up, the Fuhrer approached and patted Robert on the cheek affectionately. It was, La Rochefoucauld later recalled, a dream come true for his 15 year-old self. Hitler was then the great statesman of Europe; young Robert and his schoolmates had attached swastikas to their bicycles in admiration.

La Rochefoucauld was back in France when the Nazis invaded. His father was taken prisoner; the rest of the family took refuge in the Chateau de Villeneuve, east of Paris. Furious at the Occupation, La Rochefoucauld protested long and loud until he was warned to keep quiet by a friendly postman, who had intercepted a letter denouncing the young man to the Nazis.

La Rochefoucauld made contact with the Resistance in the spring of 1942, keen to find a route to join Free French forces in England. He took the pseudonym René Lallier and travelled, via Vichy and Perpignan, to the Pyrenees, where he accompanied two British airmen over the Col de Perthuis into Spain. Immediately arrested, the three spent two months in jail before Major Eric Piquet-Wicks, head of recruiting French nationals for SOE, arrived from the British embassy in Madrid and arranged for the three to be released.

It was at the embassy that La Rochefoucauld was invited to join SOE. "The courage and skill of British agents is without equal," he recalled the ambassador noting. "It is just that their French accents are appalling."

After meeting de Gaulle to ask his permission to join British forces ("Do it," came the reply. "Even allied to the Devil, it's for La France.") La Rochefoucauld began his training early in 1943 at RAF Ringway, near Manchester, where he learned to parachute and use small arms and explosives, as well as how to kill a man with the flat of his hand. Experienced safe-crackers were brought out of jail to show the recruits the art of breaking and entering. In June he was considered ready for his first mission.

Dropped into the Morvan with two British agents, including one radio operator, La Rochefoucauld teamed up with a Maquis group near Avallon led by a man who called himself The Pope. After destroying the electrical substation at Avallon, and blowing up railway tracks, La Rochefoucauld was awaiting exfiltration by the RAF when he was denounced and arrested. After a series of interrogations, he was condemned to death.

En route to his execution in Auxerre, La Rochefoucauld made a break, leaping from the back of the truck carrying him to his doom, and dodging the bullets fired by his two guards. Sprinting through the empty streets, he found himself in front of the Gestapo's headquarters, where a chauffeur was pacing near a limousine bearing the swastika flag. Spotting the key in the ignition, La Rochefoucauld jumped in and roared off, following the Route Nationale past the prison he had left an hour earlier.

He smashed through a roadblock before dumping the car and circling back towards Auxerre on foot under cover of night. He sheltered with an epicier. From Auxerre, friends in the Resistance helped him on to a train for Paris, where he evaded German soldiers hunting him by curling up underneath the sink in the lavatory. "When we arrived in Paris I felt drunk with freedom," he recalled.

Taking refuge with an aunt and uncle, both of whom had assumed he was dead, La Rochefoucauld spent a month rebuilding his strength before, in February 1944, recontacting SOE, which ordered him to the Calais coast, then on high alert for the expected Allied invasion, to be extracted by submarine. After a successful rendezvous off Berck, La Rochefoucauld enjoyed a convivial evening with the crew, only to find himself obliged to stay on-board for three days while the sub completed a patrol. Those days of confinement, he wrote, were among his "worst of the war". When the vessel came under depth charge attack, La Rochefoucauld noted later, he had "never been so scared in my life".

Back in London, however, he found a city celebrating a victory that many assumed was just around the corner. "We were invited to the best houses," he recalled. "Girls fell into our arms." By May he was ready to be parachuted back into France, charged with blowing up the vast munitions factory at Saint-Médard near Bordeaux ahead of D-Day.

The mission, code-named "Sun", saw La Rochefoucauld infiltrate the factory dressed as one of the workers there. Over four days he smuggled in 40 kilos of explosives, concealed in hollowed-out loaves of bread and specially designed shoes. On Thursday May 20, La Rochefoucauld linked the charges and set timers before scaling a wall and pedalling to safety on a bicycle. The blast was heard for miles. After sending a message to London (the reply read simply: "Félicitations") he enjoyed several good bottles with the local Resistance leader, waking the next day with a hangover.

Cycling to Bordeaux to meet a contact who was to arrange his return to England, however, he ran into a roadblock, taken prisoner, and imprisoned at the 16th-century Fort du Hâ.

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