I KNOW from reading the racier novels that people are often propositioned by neighbours, but it had never happened to me until a couple of months ago. The woman who lives two doors down accosted me in the street and said she had something on her mind that I would find surprising, maybe even offensive.

I grinned. 'I'm broad-minded,' I assured her, and within moments we were sitting in my living room. She is a television producer and, as media folk do, she came right to the point.

'We're looking for a voice-over for Himmler,' she said briskly. 'I've considered everyone I know and I can't think of anyone who would do it better than you.'

She was right that I would be surprised. I am not an actor. My broadcasting experience consists of occasionally presenting Granada's What The Papers Say on BBC 2, plus a few interviews and discussion programmes. Maybe I do let myself get a bit carried away on air sometimes, but how had she been persuaded that I was a natural to portray the ranting Reichsfuhrer of Hitler's SS? It cannot have been been my politics: at election times I am always pressing her to put a Labour poster in her window.

'We don't want an actor,' she insisted, 'and we don't want a German accent. We want someone with a neutral, almost a flat voice, and yours is the most . . . well, the most neutral I know. All my other friends are too Oxbridge.'

I was not sure that this was wholly, nor even partially, a compliment. But, as the song says, everybody needs good neighbours; so I agreed.

The programme is in the BBC's Timewatch history series. It is about two Polish children who were taken from their parents by the German authorities in the Forties and sent to Germany for adoption, to improve the racial stock. Himmler was the architect of the policy and, in the film, will be heard explaining and defending it.

Several weeks passed after that first approach and I thought perhaps in the meantime she had found a real pro - a Norman Tebbit, say, or a Dennis Skinner. But eventually she did phone and made a date for recording the next week. She would pick me up and drive me to the commentary studio at the BBC's Kensington House in London.

I had the weekend to get myself in the right frame of mind for my acting debut. I once read that Dustin Hoffman likes to become the person he is portraying, but I did not see how I could quite manage that in Himmler's case.

Strut around in jackboots? I doubted whether I could lay my hands on a pair at short notice. Read Mein Kampf? I do not have a copy and the politically correct Lambeth public library system may have misinterpreted the request. Smash a few Jewish windows? The only Jew I know in our Band G enclave in Vauxhall is myself, and breaking my own windows would be excessive even by the standards of the Third Reich.

I made do with shouting at my wife a bit more than usual and going to see the movie Glengarry Glen Ross, where the attitude of the company executive to his sales team has definite Fascist overtones. Another thing I did, quite inadvertently, was to pick up a snuffly cold.

The producer had thought of everything. For the drive to Kensington she had already put a tape of Himmler's voice on the car's cassette player. He was not a high-pitched shrieker like Hitler, but his calm, almost matter-of-fact delivery made the outrageous things he was saying sound even more deranged. I noted with some concern, though, that he did not appear to have a cold in the nose.

At Kensington House the producer introduced me to her colleagues. 'Done anything like this before?' one asked cheerfully. 'I can honestly say,' I replied, 'that this is my first Nazi voice-over.'

In the commentary studio's control room, bristling with levers and flashing lights, the producer asked the engineer whether he could make me sound vaguely distant. 'That's easy,' he said. 'I'll just sit him farther from the microphone.' This new technology is terrific.

I was given the script and discovered that I had six short speeches to read out. 'In the 11 years I have been Reichsfuhrer SS,' I began, sonorous but distant, 'my aim has always been the same: to attract all the Nordic blood in the world and take it for ourselves.'

There was much more in this obsessive vein. 'From these people we take those who are of good blood. We steal them just as we steal their children. The rest are a matter of complete indifference to us.'

And then: ' Brunhilde Meszysnki's children, aged four and seven, in view of their Jewish descent, are to be sterilised.'

Once I had learnt to put sufficient menace into my voice, and not to stumble over the words 'National Socialism', it all went quite well. The producer was delighted with my rendering of Himmler as a nasally challenged automaton, although she stressed that she could make no final decision on whether my words would actually be used in the programme until she matched them with her images. If they sounded wrong, she would have to try something else.

So I cannot yet be sure if, when the programme is aired in early February, mine will be the voice uttering Himmler's lunacies, or whether I shall end up on the cutting room floor. Either way, it is just possible that a new career may have opened up to me. Let me announce here that I and my neutral, chilling, adenoidal, non-Oxbridge voice are henceforth available for after-dinner speeches, extremist rallies, weddings, bar mitzvahs . . . or maybe not bar mitzvahs.

(Photographs omitted)