Sylvester McCoy will always be my Doctor. This is partly because he appeals to my maternal side: with the other Doctors, they’re heroic and I dream one day they may rescue me. With Sylv, I want to smash the TV screen and rescue him. But when the show was suspended in 1989 – with no official announcement, and no explanation - I felt bereft. I hadn’t had time to grieve for him properly: to see him regenerate. And when it came back in 1996, it wasn’t the same show: it was some weird American spin-off. So I’ve always wanted to see him be a Timelord on television one last time, and now I’ve finally made it happen…in the BBC1 daytime drama series, Doctors.

Yes – on Monday 13th October 2008, for one episode only, Sylvester McCoy will play a time travelling eccentric…on the run from his own people, and lying low on the planet Earth. Well, that’s not quite accurate – he plays an actor, who used to play a time-travelling eccentric on children’s television, in a show called The Lollipop Man. And yes, The Lollipop Man is a thinly-veiled version of Doctor Who (though in tone, it’s more of a kids’ show…closer to Catweazle or Supergran) and Sylvester plays a character called Graham Capelli who perhaps has a tiny touch of Sylvester in him. His life these days consists of being dragged to DVD commentaries that he can’t quite get the hang of, and putting his Lollipop Man’s coat on for conventions, despite the fact that he can’t do the buttons up. Only he’s heard that they’re going to be bringing the series back, and he’d quite like to be a part of it…

So that’s the basic gist of the story I submitted (in April this year), and when it was commissioned, naturally I wanted my Doctor to play the Lollipop Man, but you have to be a bit careful when making suggestions to TV people: they don’t like to be taught their jobs. However, when it got to the casting stage, I had an e-mail from the script editor, Neil Irvine, saying: ‘Would it be too cheeky to ask an ex-Doctor Who to do this?’ And my heart skipped a beat, but I didn’t want to play my cards too close to my chest, so I wrote back: ‘Well I suppose there’s always Sylvester McCoy’. And of course, it turned out, Sylv was his Doctor – the one he grew up with, his hero, his favourite actor. When the script was sent to Sylv, I don’t think I’ve ever been so nervous: I paced up and down for several days. I’d have felt so humiliated if he hadn’t liked it or had refused to do it…I’d have still watched his DVDs and gone to see him in plays, but with a slight rictus grin on my face and a little knot in my stomach.

But seeing him work on my script made me realise why I fell in love with him twenty years ago and why I still think he’s one of the best actors in the world. He just has a brain that never stops fizzing, and enough energy to power the National Grid: there are so many tiny moments in the story that he turns into huge, important ones. In the script, he arrives at the health centre and produces his appointment card…naturally, being Sylvester, he produces it via a conjuring trick from behind the receptionist’s ear. Sylv’s character is off to record a DVD commentary, though because he gets confused with words, he calls it a TV coronary before finally settling on DVD cemetery.

When I first saw Sylv speak these lines, I could swear he was genuinely confused and grappling for the right phrase: as an actor, he totally exists in the moment – it’s like watching a child playing. He’s got such warmth and vulnerability. And it is a part where he has to expose a lot of himself: he’s playing a clapped out old actor who used to be a sci-fi hero on children’s television. I worried that instead of accepting the part, he might have tracked me down and strangled me with his bare hands. But he must have found something in the character he could connect with. At one point in the episode he gets into an argument with a TV producer and tells her: “I’m fed up being told what to do by twelve-year-olds” and you can see such seething rage behind his eyes. In many ways I think he’s a better actor than he was twenty years ago. He’s now got the looks for it – a craggy face with fantastically furry eyebrows…he has the features for all the interesting character parts which I hope he’ll get over the next twenty years. He wasn’t treated terribly well in Doctor Who and to my mind didn’t get a proper exit. But many of the people who watched him twenty years ago as kids, are now grown-up and have the chance to create amazing work for him.

The fictional show I invented within my episode – The Lollipop Man – is about a time traveller who, whilst hiding out on earth, gets a part time job as a school crossing patrolman, but his lollipop stick can take him anywhere in time and space: so he takes children on amazing journeys…he mostly takes them on journeys of self-discovery, so, for example, with a child who’s upset because his granddad has died, the Lollipop Man takes him back to the Second World War, where he gets to meet his granddad as a small, scared evacuee…and they get to play together one last time, even though it’s a kid his own age he’s playing with. That’s what the Lollipop Man does – he helps people over the road, both literally and metaphorically. And that’s what Sylvester did for me twenty years ago: he helped me through a difficult patch in my life, and when the world around me seemed bleak, he was there, full of colour, full of inventiveness, full of hope.

Thanks Sylvester.

Doctors: The Lollipop Man is on BBC1, on Monday 13th October 2008 at 1.45pm.