Doing the Hercules show (sudden surge in numbers yesterday to over 70, but back to around 40 tonight) has made me realise the number of people who have secretly been playing various versions of CNPS over the years. A surprising number of people tell me that they played as a child or that their dad or uncle has been round the CNPS clock two or three times. Of course my publicising the game and solidifying the rules have led to a whole new generation of players (many of whom are about to meet the brick wall of the emergence of the new style number-plates and have no realisitic chance of ever finishing the game).

My friend Simon came to the show on Tuesday and has just emailed me these scans of his I-Spy Number Plate book. Now, I'm not totally sure, but I don't think this was the book from which I learnt of the game. It's an outside possibility as like most kids of my generation I did have a lot of I Spy books and I was interested in number plates, but I'm pretty sure my version was in a proper paperback and went into a bit more detail about the game. Also in this version it's something you merely play til the end of a journey, not a life-time's obsession. Still it's an interesting document to have. And that picture of the child standing on the car seems eerily familiar, so who knows? Actually it's quite chilling isn't it? The way it is inappropriately standing on the car and looking so haunted whilst the other 70s figures are having fun. Like some kind of ghostly figure from a previous age who was maybe run down by the SPY 999 car and now haunts it and messes around with the radio reception at every given opportunity. The other people in the photo can't see this spectral child. Only we can. And it is too late to warn the happy adults that their next car journey will end in their own deaths as a childish voice repeats, "Why did you make me go hurt? Why?"

I do love the slight desperation of some of their number plate game ideas. To be fair it must have been hard to come up with a whole (even tiny) book's worth. Number 3 there is a bit pathetic. Will you be surprised what exciting messages you can make? Or will you in fact be slightly bored after about thirty seconds of this nonsense?

Number 4 is especially desperate. The writer obviously found out that Jimmy Tarbuck has the number plate COM 1 C and thought there might be some mileage in it. "COM 1 C for instance belongs to comedian Jimmy Tarbuck," writes the author. I would have more respect for this game if the inventor of it had managed to come up with a few examples of other famous people with unusual number plates. But the fact is that Jimmy Tarbuck, at time of publication, was the only one. What are the chances of a child happening to pass Jimmy Tarbuck on a long car journey? Very small. Let's imagine there were other 70s celebrities with personalised plates that happened to coincide with their jobs and give you a clue to their identity. Even if there had been 100 of them you would only get to see one every ten years or so (at a guess).

I would have even more respect for the I-Spy series though if they had stuck to their guns and made children play this impossible game of hunt the Jimmy Tarbuck's car in the haystack made of cars instead of hay. But no, they lost their bottle and essentially admitted it was a rubbish game by adding the additional sentence, "Or invent possible owners; does CAT 21 belong to a vet?" That is just shit. And no, it doesn't. I don't know how many vets went for personalised number plates in the 70s, but I am guessing any that did, a) probably didn't draw attention to their job when doing so and b) if they did would not have wanted to show preference for one animal when they work with so many different breeds. I would have said, "Does CAT 21 belong to Cat Stevens? And he's still driving the car he had before he changed his name and can't afford to change it?" Or "Does CAT 21 belong to a cat that has amazingly developed the ability to drive and the money to both afford a car and a personalised number plate? He was probably left the money in a will by an eccentric old woman. I bet he was gutted when he found there were twenty other cats already driving on the roads."

If a vet really wanted to draw attention to his job I think he would have gone for the number plate "VET 21". Although this line might have also been bought up by Viet Nam Veterans, so you'd have to look closely into the driver's eyes to work out which it was.

"See how many famous people you can "collect" or "invent" on one journey," advises the book. I am guessing you will "collect" none and probably "invent" maybe one, before getting bored, growing up and realising that you were being tricked by adults into being quiet and distracted on a car journey.

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