David Niven opened the door to his suite at the Connaught hotel wearing just a small towel around his waist, revealing surprisingly muscular legs and arms, even at 60. “Do excuse me, gentlemen, I had to have a quick shower or I’d give off an awful pong. Been exercising, you see.” He did a little weightlifting movement.

“Pumping, you know,” he said with a grin.

I became aware of movement and saw a half-naked young woman tiptoeing around as she collected her clothing. “She’s the cleaner,” said Niven, deadpan. “Only she makes more mess than she clears. Anyway, do come in, gentlemen.”

The gentlemen were me, just turned 18, and my boss, the distributor of Niven’s latest film. I was little more than a messenger boy and trainee junior publicist. David disappeared into another room to get dressed. The girl was completely unconcerned by our presence, and by the time he reappeared, buttoning his shirt, she was ready to go.

“I do hope you won’t be late, darling,” he said to her. “No, my audition won’t be for another hour,” she said, and left. A few years later she became quite a well-known actress.

I was there to do a publicity biography of the star. I discovered that I didn’t need to ask too many questions. David loved to talk. And talk. I hadn’t realised he would be so funny, or that he was such a randy fellow. Between that year, 1970, and his death in 1983, I interviewed him seven times and, by pressing him further and harder, discovered the man behind his own myth.

He certainly benefited from playing fast and loose with the facts, making a fortune from writing The Moon’s a Balloon, the most entertaining autobiography ever penned by a Hollywood film star. But although he didn’t seem to know it, his real world was every bit as entertaining and rich and fascinating as the one he’d invented.

Our last interview, in 1982, was the most revealing, shocking and emotional. Motor neurone disease was slowly taking him. He was 72 and looked 10 years older. He called me and said in a slurred voice: “I need to see you, Mike. And bring a tape recorder.”

At his Mayfair flat he warned me not to make him laugh because he had lost control over his facial muscles and laughing made him hysterical with tears running down his face.

“My face becomes so contorted that I look like someone dying of laughter and crying in agony,” he said. He proceeded to tell me about such bizarre and hilarious treatments given him by quacks that we were soon both laughing. I saw what he meant by his face being contorted and how the tears flowed.

He finally got around to the reason he had wanted to see me. He said: “You’re exactly what I need — a friend, an author and a priest.” I had been an elder in the Mormon church for two years. I no longer believe what I did then, but my faith was important to him. “I don’t know how long I have to live,” he said. “Maybe only months. I don’t feel I want to meet my maker without having got a few things off my chest.”

It was a dying man’s confession: the real Niven.

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