A FEW DAYS after the liberation of Naples a young British Army officer was strolling through the city’s streets when he came across a startling sight. It was a majestic old theatre — locked, silent, abandoned and distressed. A bomb had ripped away its foyer, bringing the roof crashing down. Piles of masonry blocked its grand entrances. Its walls were scarred with bullet marks from the recent battle.

The officer, Lieutenant Peter Francis of the Royal Artillery, had no special knowledge of Italian opera houses. He barely recognised the name on the torn posters among the debris — Teatro di San Carlo. He certainly didn’t know that he had stumbled across what is arguably the oldest working theatre in Europe.

Even so, he was intrigued. A non-smoker, he produced 50 army-ration cigarettes and bribed Giuseppe, the ancient stage doorkeeper, to let him in. And so began one of the strangest chapters in the history of the Second World War: the story of how a 26-year-old British anti-aircraft officer found himself running one of the world’s great opera houses.

Today, Francis (now 86) lives in Poole. In civilian life he became general manager of the Southend Water Company, then took early retirement and went into the travel business — running, among other things, opera tours to the San Carlo. It is 60 years, almost to the day, since he stepped into that theatre. Yet his memory of that moment is as vivid as if it had been yesterday.

The sight that greeted him inside was tragic. Rubble was piled high in the corridors. Dressing rooms and stores were unusable. The famous auditorium was coated in debris and dust, its top balcony largely collapsed. And the stage grid was a tangle of snapped wires and smashed pulleys, the result of Allied aircraft strafing a German machinegun post on the roof.

Francis saw all this by the shafts of daylight piercing the damaged balconies — the electricity supply was dead. Yet his reaction to the magnificent interior, with its glorious painted ceiling and six tiers of boxes, was much like Stendhal’s when the French writer had walked into the San Carlo in 1817: “There is nothing in all Europe which gives the slightest idea of what it is like . . . it dazzles the eye, it enraptures the soul.”

Francis was also dazzled and enraptured. “I said to myself: ‘What a theatre! We must get it open.’ ” He went to see his brigadier, who took the matter to the area commanders. “A day or two later the word came back: ‘Only too pleased; give the troops something to do’. And that’s how it started.”

Today, the restoration of an opera house takes years (Venice’s La Fenice is only now reopening after its 1996 fire). But in November 1943, in a city short of the most basic materials and with the front line just 30 miles away, Francis achieved a sort of miracle. He had the San Carlo open in just two weeks. And, remarkably, he did it without being able to speak Italian (“I’m told I speak it now with a strong Neapolitan accent,” he says).

Word quickly got around that a mad young Englishman was trying to get the city’s grand old theatre on its feet again. Gradually its former staff, who had been unable to work there for more than a year, drifted back.

“The first to return was a tenor called Ettore Ponno,” says Francis. “Luckily, he was married to an Englishwoman, so his English was pretty good.” With him as interpreter, Francis was able to round up the old stage crew. “They were so overjoyed to be back that they worked incredibly hard to repair the stage machinery and lighting.” The most pressing problem was the power supply. “At that time most of Naples was running on the generators from submarines,” Francis recalls. So he cheekily invited the adjutant general to the reopening gala. As if by magic, the San Carlo was immediately provided with its own generator.

Similar tactics got the foyer rebuilt. “We needed cement, and the Navy controlled the big cement works. So I promised their top brass some tickets for Gigli singing Aida.” The cement arrived molto prestissimo.

Wood, canvas and wire were scrounged, begged or strong-armed from around the city. Francis marched a column of troops up to the music conservatory to requisition a grand piano. Squaddies were detailed to clear the debris. The owner of what Francis describes as “Naples’s equivalent of Liberty’s” was strongly encouraged to replace the theatre’s drapes. Finally, the San Carlo’s celebrated front curtain — a spectacular painting of Parnassus by Giuseppe Mancinelli — was brought out of its wartime hiding-place and proudly rehung.

Making the theatre usable was one thing. But then Francis had to find a show to put on. His first notion was to involve Ensa (officially, the “Entertainments National Service Association”; unofficially “Every Night Something Awful”). But Ensa quickly decided that running the San Carlo was too big a task. So Francis, undaunted, decided to go into showbiz himself.