Two things have amazed me about the coverage of the John Darwin story this week the sheer scale of it, dominating everything else that has happened in the world, and the fact that everyone has related it to Reggie's disappearance in The Fall and Rise of Reginald Perrin 31 years ago. There is something about disappearance that fascinates us, and I have been trying to work out what it is.
When I wrote the first draft of the novel on which I based the series, Reggie didn't even disappear. His breakdown led him to a mental home. This didn't work at all. If a character is going mad, the worst place a writer can send him to is a mental home. For drama you put mad people into a sane world, and sane people into a mad world.
I can't even remember the moment when I decided that the solution to my story of a man driven crazy by the routine of his life was for him to leave his clothes on a beach and set off for a new life. I wouldn't have believed it if someone had told me that the phrase "Doing a Reggie" would enter the language, and that in 2007 I would have become a sort of unofficial Head of Disappearances.
I must take this opportunity to clear up one misconception. I did not get my idea from John Stonehouse, the Labour cabinet minster who left his clothes on a beach in Australia. Nor did he get it from me, unless he had access to my manuscript, which my agent was touting from publisher to publisher, many of whom, in the classic tradition of such things, turned it down. No, he left his clothes on that Australian beach after I had written the book and before it was published. It was one of those moments when there seems to be some uncanny relationship between fact and fiction.
After the book had been published, and even more so after the first series of the TV show had been broadcast, I began to get letters, all of them from men who identified with Reggie in two respects and who asked me for my advice. For a while there were so many that I found myself looking in the mirror to make sure that I hadn't turned into Claire Rayner.
These men all felt the same existential discomfort with their lives as Reggie. They felt that there must be something better, some different definition of themselves and their lives, if only they could find it. They longed to escape; they were pretty sure what they wanted to escape from, but they didn't know what they wanted to escape to. Could I help? Could I advise? Should they escape?
I was vaguely flattered by these letters, but also disturbed. I didn't know enough about their lives to be able to offer concrete advice. I took refuge in pointing out that Reggie found that there was no escape for him. He was Reginald Iolanthe Perrin deep down, however much he might change his name. The thing was a great illusion.
The element that all these letter writers had in common was disillusion with their work. It is an unavoidable fact that millions of people in our society are in jobs that do not fully satisfy them, simply because there are millions of jobs that by their nature cannot satisfy a well-balanced but imaginative and ambitious person.
But they were all men, and even in 1976 many women would surely be feeling frustrated and trapped in their jobs. Why did none of them write to me? Why, even more pertinently, are all the people who "do a Reggie", as far as I know, men?
This is all a far cry from the present case, which, as it unfolds, becomes more and more like a slightly overwritten film script, which it will surely soon become. It's full of artistic touches, the damaged canoe, the run-down flat in Panama, the fatal photograph, the disturbed sons, the walking into a police station, the amnesia, the hiding in the wardrobe.
Amnesia is another unbeatable subject for fiction, and I think this is because it touches upon a very deep fear. A French chef once promised a friend of mine the most memorable meal of his life. Unfortunately, he took so long to cook it that my friend got so drunk that next morning he could not remember having eaten it. There is no value whatsoever in an experience we can't remember.
The more elderly among us fear Alzheimer's more than anything, but the fear of emerging from some accident unaware of one's identity is terrifying, and is in a way the opposite of the urge to escape. One has not escaped one has been expelled, and one has no idea what one has been expelled from.
Before I leave the Darwin case I must touch on the possibility of his having feigned amnesia. How difficult is that? It must be almost impossible to remember exactly how much one is supposed to have forgotten.
Reggie's attempt at escape in 1976 seems so innocent now, a philosophical act, much more interesting to me than an insurance scam. I suppose if I was writing it today I would have to include a thorough police investigation. In 2007, we never believe the facts with which we are presented.
So why does it seem to be only men who "do a Reggie"? There has been a critical study of Perrin explaining it all in Marxist terms. I read it with great pleasure because I hadn't realised how clever I had been. But there has never been an explanation in Freudian terms. I do suspect, though, that male sexuality is very germane to the disappearance phenomenon.
The male sex drive is so much more a matter of physical attraction, and so much less a matter of emotional attraction, than the female sex drive. This is a generalisation, so it will not be true in all individual cases, and it's a tendency rather than an absolute fact, but my contention is that sexual dissatisfaction is a part of the cocktail that fascinates us with the idea of escape. Adultery is commonplace, tedious, banal, awkward, leads one into a web of deceit and is usually destructive. But escape, with no ties, no complications, no need of any lies except the one great enormous fact that one's whole new life is a lie, how tempting that is.
I have talked to a lot of people who readily admit to being fascinated by the possibility of escape, who dream of it in the bath, who ride out on a bike on a sunny spring morning and contemplate the possibility of just riding on and on, away out of their own lives into the sunrise.
It has even been suggested to me that everybody, or at least every male, has at one time or another felt this. I don't believe that for a moment, but I do believe that the dream is an extremely common one.
Surely Gordon Brown must wake up some mornings and think, "If only I was called Tommy Cosgrove and was running a beach bar on Skopelos."
Every time I am dragged out and interviewed about "doing a Reggie" I am asked if I have ever contemplated it. At such moments I think of dear Leonard Rossiter and feel a wave of loss. I have heard him asked that very question and I have heard his scornful reply.
"No, dear. I am an actor. I have played Macbeth but I have never wanted to kill anybody. I have played Hamlet but have never wanted to kill myself. I am an actor."
The question is not so silly when put to a writer, however. People are entitled to ask whether there must be something of us in everything we write. The answer is still "no" but the question is worth asking.
And my answer? No, I have no urge to escape. I have no need to. I write fiction. I can escape any time I want, for as long as I want, and return when I want. Oh, how good that is, and in realising how good it is I understand how powerful is the dream of escape, and why we are so fascinated by stories of disappearance.
Further reading: The latest book by David Nobbs is 'Cupid's Dart'. It is published by Random House, price 17.99