WHEN BBC TWO'S Culture Show asked whether I'd be willing to be filmed secretly watching a Wolverhampton book group discuss my newly published family memoir, If You Don't Know Me By Now, I was torn.

On the one hand, the publicity might be good for sales. But on the other, given that the book contains a description of my home town as “the arse of the Black Country, in itself the bumcrack of the West Midlands, in itself the backside of Great Britain”, it was quite possible they would hate it. Also, given the intensely personal nature of the subject matter, I was concerned I might end up crying or punching individual book group critics in the face when the moment came to reveal my presence.

Indeed, the whole idea raised uncomfortable memories of that notorious 1990 episode of BBC Two's Jukebox Jury, in which various panellists slated a new single by Glenn Medeiros, only for Glenn to suddenly appear on set as the “surprise mystery guest”. The incident, recently ranked No 55 in the Greatest TV Moments from Hell, instantly destroyed his British pop career. But somehow, after a discussion with the producers and my publisher, I found myself agreeing to do it.

I lost my nerve just days later when the programme makers called to say that they wanted to tinker with the format: how would I feel about sitting, surreptitiously, as a member of the book group, instead of watching from another room? It didn't take long to provide a response: I'd feel terrible, of course. My acting skills were lame and I was bound to give the game away instantly.

The producer responded to my objections calmly. I would be disguised. The book sleeve that had my picture plastered on it would be removed on the copies given out to the group. And it didn't matter if I was spotted - it would be good telly.

Unfortunately, very little of what happened in the hours before the book group meeting in increased my confidence. We spent the day shooting footage around town. Outside Wolverhampton Central Library, I avoided being spotted by the chairman of the book group only by fleeing into the reference section. And when it came to establishing a disguise, the otherwise sane and charming director suggested - not entirely seriously, I hope - that I don a turban, as a key chapter in the book describes how I had my topknot chopped off at the age of 14.

In the end, we settled for something distinctly less ambitious: I would take my spectacles off - it worked for Superman - and put on the sound assistant's jumper. It was agreed that I would introduce myself to the group as one Harjit Mann, and that I could reveal my real identity at any point I wanted, if the hammering became uncomfortable.

I don't have great recollection of what happened because it was the most stressful half-hour of my life, and all I cared about at the time was that the book group didn't immediately spot me and that they all seemed to enjoy the book.

But running over it in my mind, I do remember getting a little carried away slagging off my own work - I thought it would be the best way of concealing my identity. I remember being taken to task for my portrayal of Wolverhampton and arranged marriages. And I remember trying but failing to do anything about my ears, which glowed bright red throughout filming, no matter what I put against them.

Of course, the gaps don't matter because the cameras caught it all and you can see what happened for yourself tonight on BBC Two at 7.10pm. If I can bring myself to watch, I'll be doing so through my fingers, my head in my hands, praying that the publicity might, at least, be good for sales.

If You Don't Know Me By Now: A Memoir of Love, Secrets and Lies in Wolverhampton by Sathnam Sanghera
Viking, £16.99; 336pp

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