The lurid TV murder drama has become a parody of itself, with increasingly elaborate and disgusting cases and ever more unstable detectives. It's hard to take seriously. Can widowed, hard-drinking, emotionally volatile maverick DCI Jack Cloth and the chalk to Cloth's cheese, emotionally closed ice queen DC Anne Oldman, rescue the genre?

Not on your life: they're here to bury it, because while Sky1's A Touch of Cloth has every trope in place, it's all there on purpose. This is a deadpan, joyously silly Naked Gun-style parody conceived by Charlie Brooker, in which John Hannah and Suranne Jones mercilessly send themselves up.

"I like dark crime dramas," Brooker tells Radio Times about the genesis of the idea. "Se7en is one of my favourite films. But it seemed every weekend had a dark TV detective drama involving someone like Robson Green that smacked of an excuse to put as much horrible stuff on the screen as possible. Everything has to be bleak and sombre and everyone's life is destroyed."

Once Brooker had the idea to spoof doomy detective sagas, he noticed that, while they were all trying to stand out from the crowd by having the craziest cops and the most unhinged killers, in fact they were all the same. Everything from the crime scene to the confession followed a formula.

A Touch of Cloth stretches the familiar just a little, throws in some slapstick, sight gags and silly wordplay, and turns cop-show cliché into a comedy franchise that could run for longer than Taggart. The first feature-length story will be shown, Silent Witness-style, in two parts this Bank Holiday weekend, with a second already in the can and a third commissioned.

To get to the essence of absurd serial-killer dramas, Brooker and his co-writer Daniel Maier sat down and brutally dismembered them. "Rather than watching things from beginning to end, we had a compilation of crime scene discoveries, of interrogations, of morgue scenes. Shorn of the context of the surrounding programme, they become very funny. You notice things you don't notice when you're caught up in the story."

What about those classy subtitled dramas a lot of us are very pleased with ourselves for watching? They're a cut above… aren't they? "I enjoyed 75% of The Killing – it went on a bit – but I didn't think it was much different to a BBC1 or ITV1 crime drama. You could put it on a terrestrial network on a Sunday.

"One that really made me laugh was Sebastian Bergman. If you'd said at the start, here's a spoof Scandinavian crime drama, you'd have had a hit on your hands."

While Brooker admits that, because he can now "see the workings", he can laugh at the grimmest murder stories – he cites Cracker, Silence of the Lambs and even Appropriate Adult – this comedy generally keeps it light and silly. "There are a lot of stupid jokes which you could show at 6pm. You'd just have to cut out the morgue scenes and the gore."

Serious crime dramas might all be piles of ludicrous clichés when you look at them closely, but Brooker doesn't blame them. "There are weird things that happen in any programme that don't happen in real life. They all have to do certain things. They're genre pieces: you accept when you watch that they're going to have that format.

"This isn't a spoof borne out of hate. We're just pointing out that it's all about as realistic as a scene where a person flies to Venus."

CHARLIE'S TOP COP CLICHES

Hot in the morgue
"There's always someone in the morgue eating a sandwich or something. And there's the forensic pathologist who is a bit arch and glamorous. Sort of sexy, and nonchalant about the gore. There's always a bit where they're looking at a naked woman. It's an excuse to show pubic hair on television. Somebody called it "the blue tit scene" as they all sadly look at a beautiful woman who's been hacked apart. To think I worry about teenage boys growing up with easy access to pornography on the internet – when I was 13, most naked women I saw were dead on slabs on television. What must that do to someone?"

Crime scene: exposition
"We watched about five identical scenes from Wire in the Blood where Hermione Norris turned up at a crime scene, and a man in a mac greeted her and walked her up to where the body was, spouting statistics. He'd never say hello. She'd step out of her car and he'd immediately say: 'Melanie Francis, 34 years old, found by a man walking his dog…' and continue this exposition-blurt all the way to the corpse. Then he'd vanish. That's where Asap Qureshi (Navin Chowdury) came from. We thought, we need a man in a mac who spouts facts."

Murder mystery
"Cops trying to solve what the murders mean. What message is the killer trying to send us? It's like going through Kit Williams' Masquerade or rubbing your hands with glee as you approach the cryptic crossword. If we can crack the clues, we can understand where the killer is coming from. Has that ever happened in the real world? A murderer leaving a trail of artworks behind? Most murderers are just very disturbed. You might build up a psychological profile, but they're not leading us on a merry dance. So there's a scene in Cloth where it's like they're playing Only Connect. 'Is it… the Mister Men?'"

Thinking clearly
"There's always a scene where they're standing in an incident room looking at glass board. Once you realise why it exists, it's obvious: it's so the director can shoot through it. You don't question it for very long watching Waking the Dead, but there's no practical reason at all to have a see-through noticeboard in a room. It would just be annoying. You'd have a whiteboard on the wall. But it then infected Crimewatch – they started having see-through boards in the background. Stop it! It looks very strange, but maybe Crimewatch now think it would look strange if they didn't have them."

Grime and punishment
"We've gone for the sink-estate opening. Everything looks awful, everyone is miserable, there's a man beating a pram with a cricket bat. We had to take out a close-up of that, it was felt to be a bit too much. He's still there but you have to spot him. What we didn't get is a scene of them trying to interview a single mum on her doorstep while a baby cries in the background. 'Shut up Tasha!' There's a scene in a youth club where if you look carefully, people are being taught to assemble petrol bombs and inject heroin. That's another cliché: youths are all thick and heartless, they come from hell and they don't really care about anything."

Good cop… gone bad
"Cloth is a broken man. That's a constant. You can't have a policeman who solves horrific, harrowing murders and then goes surfing. You always have to show the psychic price – the ultimate cost of putting these people away. Real cops have to adopt a businesslike approach, but that doesn't make for a compelling character on television. They conduct interrogations that border on psychological beatings. Cloth loses his rag with a suspect very early on so you think, my God! This man is a loose cannon! The exception to the rule is Saga in The Bridge. She was basically C3PO. That was a clever subversion of the norm."

A Touch of Cloth series one is available on DVD now.

Watch the trailer here: