The last time Shoestring was repeated on TV, a few years ago now, it was screened in the Diagnosis: Murder slot on BBC1 weekday afternoons. If you’re an anorak, you may be thinking that, hang on, Diagnosis: Murder is a US series so its hour probably only runs 42 minutes or something, but Shoestring was BBC 1979, it’s a full fifty minutes and change.

You’re perfectly correct and, may I say, remarkably well informed. Plainly, 50 into 42 doesn’t go all that well, but the BBC wasted no time thinking about it, they just chopped eight minutes or so out of Shoestring. That’s what, 16 percent? You can argue all you like about how that would be vandalism if they’d done it to someone else’s show, it’s astounding to do it to your own, but you wouldn’t argue that it really made a difference to the series.

You wouldn’t argue it at all because it there’s no counter-argument: take nearly a fifth out of your story and it isn’t going to survive. And, yes, the episodes that aired then were incoherent messes; I watched the first couple and walked away.

But BBC4’s just been celebrating Shoestring with a repeat of one episode and a half-hour documentary. In between the last screening and this I’ve interviewed Trevor Eve and don’t ever wish to do that again, so maybe my old fondness for the show had been a little bit scorched. I still expected to like it more than I did.

I did like the feel, I did like the characters, and I liked how it reminded me of so long ago in my life. (Just as an aside, I vividly remember listening to the last-ever episode of Shoestring. Listening. Not watching. The tube had blown in our TV set. Do you even remember tubes? And why did “the Tube” become a nickname for television in the States but not the UK? Was YouTube’s name a mystery before you read this?)

But the actual mystery in this detective episode wasn’t much cop. Trevor Eve was good, I’ll give him that, and the steps, the process, the characters along the way, it all worked well. Only, you knew who the baddie was right from the start.

I dug out an ancient VHS copy I’ve got of the first episode, Private Ear by Robert Banks Stewart, and it was actually much the same. I’d like to have written it, there was a lot going on, but you were also just waiting for Eddie Shoestring to join enough dots that he could leap to the baddie we’d spotted at the top of the hour.

Is it inevitable on a TV budget? You’ve got your regular characters, the victims of whatever the crime is, the villain and – if you’re lucky – enough money left over for a red herring, but that’s it. If you believe plot is all that matters then you and I part company here, but I’m back with you if you’re arguing that an hour of watching characters do nothing is enough to make you watch The Bill. I’m almost with you, anyway.

I never try to figure out the crime. I rarely need to guess the baddie. The tale is in the telling, and I don’t know how it’s done.

Sure, there’s Columbo: the open book mystery is immensely refreshing both because that show was really about pitting two great characters at each other’s throats for 90 minutes, and because it also meant the series completely erased the whole problem of hiding the baddie. And then there’s Homicide, the wonderful Homicide: Life on the Street. That worked because the show was usually not about the murder being investigated and it was invariably never about the psychology of why someone murdered someone. Seriously: it was in the format, otherwise known as David Simon’s original book. Forget the why, find out how and you find out who, case closed.

But in a straight police procedural, a precinct drama, how do they successfully juggle a mystery with a budget that’s incapable of hiding the guest star baddie?

I can think of ways, I can think of misdirection, but they’re not ways that seem to get used – and they’re not ideas that could work week after week.

I’m looking at my shelves where without turning my head very far I can see DVDs of Campion, Magnum PI, The Rockford Files. I’d like to say that I’m seriously analysing a tremendously popular and often fantastically rewarding genre of television drama, but maybe all I’m really saying is that I fancy a Remington Steele marathon.

Wadday say? Want to join me?

William