I had thought that my days of being approached by reality show producers hoping to put together a cast of D-list celebrities were behind me. Apparently not. A couple of weeks ago, I was contacted by the makers of The Jump, a Channel 4 programme in which assorted ‘personalities’ try their hands at various Alpine sports, including downhill slalom, bobsleigh racing and ski-jumping. I’d never heard of it, but it sounded like fun so I told my agent to set up a meeting.

I thought the reason I must be back on the reality show radar was because I’ve published a book this year. Then, when I watched the first episode of I’m A Celebrity… Get Me Out of Here, I realised what was going on. I’ve reached the age where I’m eligible for the role of ‘token old guy’, a reality show staple. Last year, that part on I’m A Celeb was played by fashion designer David Emanuel and this year BBC broadcaster Michael Buerk has drawn the short straw.

It’s not an easy role to play. You’re allowed to make the occasional curmudgeonly remark, but in general it’s less ‘grumpy old man’ than ‘wise old bird’. When patronised by some half-witted ex-boy-band member, you’re expected to laugh self–deprecatingly, only to take them under your wing when they burst into tears a few minutes later because they miss their mum. Flirting is OK, but only with the ‘glamorous granny’, another fixture. If you so much as glance at the ex-glamour model — which is difficult to avoid, because she’s usually wandering around in a ‘jungle bikini’ made of twigs and leaves — you’re immediately branded a ‘dirty old man’. Any expression of sexual desire at all has to be of the music hall, ’Allo ’Allo! variety. God forbid that you might be a real-life human being instead of a ‘national treasure’.

But the hardest thing about being on a reality show for the over-fifties is not being able to read. I discovered this rule when I was summoned by the producers of I’m A Celebrity about ten years ago. I went along to ITV’s headquarters on the South Bank determined to impress them, mainly because I needed the money, which my agent described as ‘low six figures’.

But I couldn’t conceal my horror when they told me that books were strictly verboten in the jungle. This is partly because watching people reading doesn’t make for very exciting television, but mainly because they want the contestants to go stark raving bonkers. After two weeks of listening to an extra from The Only Way Is Essex talk about their make-up routine, you’re willing to do just about anything to relieve the monotony, including eating kangaroo testicles.

Or choreograph a musical. In series three of I’m a Celeb, token old guy Mike Read became so deranged with boredom that he decided to mount a production of a West End musical, involving daily rehearsals and an improvised jungle orchestra. The producers decided not to broadcast any of it for fear of being sued for breach of copyright, but mercifully they didn’t tell Read this so he carried on regardless. Incidentally, this was before Read had ruled himself out of ‘national treasure’ status by recording Ukip Calypso.

The irony is that a series of I’m A Celeb made up entirely of token old guys would be a must-watch. Imagine the quality of the conversation, not to mention the arguments, if you rounded up Alan Bennett, Michael Gambon, Jeremy Paxman, Bobby Charlton, V.S. Naipaul, John Cleese, Paul Johnson and Denis Healey. Of course, you might be hard pressed to persuade them to spend three weeks eating rice and beans and sleeping under the stars in the Queensland outback. But there’s no reason why the Garrick Club couldn’t be transformed into the Big Brother house. I also like the idea of throwing in a ‘token young guy’. Peter Andre could don a tailcoat and spend his time bringing the rest of the cast an endless stream of whisky and sodas.

On Tuesday morning, my agent forwarded a message from the ‘talent co-ordinator’ of The Jump. ‘Unfortunately, we are not going to be able to make it work in this year’s cast,’ she wrote. ‘I am not sure if he wanted to do it but wanted to let him know now out of courtesy.’ I clearly have some work to do on my ‘charming old rascal’ routine.