Interrogation question of escaping the cliches

I have long pondered the fact that cop and medical shows are so popular with the makers of telly. The reason I've had time to ponder this fact is because cop shows are, mostly, tedious, and medical dramas either so tedious or so bloody, I have plenty of time to spend pondering because I can't look at what's happening on screen.

Either way, they're popular with programme makers because they're an easy source of manufactured tension. It's formula telly: put a bunch of folks in the same work place. Add drama because of the nature of the workplace. Done badly, this is the telly place where they grow cliches. Done well, well, ditto - but good writing can save the thing.

On Prime's first local drama there are cops. On last night's first episode of Interrogation (Wednesday nights, 8.30) there wasn't much blood, but there was pooh.

Pooh and a car chase. What a novel beginning. There was a car chase and, somehow, a lagoon full of sewage. Which means stinker lines, as in: "I reckon you should get this guy on suicide watch and it's not the only thing that stinks. Dean, you really need to take another shower."

This line was delivered by hard bitch, Detective Sergeant Angela Darley (played by Luanne Gordon), one of those lady cops who live for the job. Angela is harder than the blokes and an old hand at interrogation. Like most cop dramas, Interrogation is big on interrogation. There must be a rule somewhere which says you can't make a cop drama without having the scene where the coppers enter the interview room and state their names and the time to the tape recorder. That rule is well and truly ticked off.

There is also a rule which says you can't make a cop drama without a character saying: "We've got him bang to rights." Do real cops really say this? I really want to know.

"Him" was the car driver who had mysterious and mysteriously fake-looking tatts: the Silver Fern and a an AB+. This allowed for a red herring to be tossed into the mix. Could the suspect be a former All Black? He turned out to be a soldier. Or, as Angela put it: "You're a Siberian racing sardine, that's what you are. You're a bloody soldier."

"Siberian racing sardine?" her sidekick asked. "Where did that come from?"

"Dunno," said Angela, "it just seemed to suit him." How very mysterious.

Turned out tattooed man's wife and kid had been murdered and the bloke who set it up had walked free. Racing sardine man had taken his revenge: kidnapped the crim and buried him in a coffin with an air pipe on a beach. The race was on to rescue him before the tide came in. Aah, but should the bastard be rescued? That's another tick: for moral dilemma.

None of this is terrible, not quite, although the characters are terrible cliches. Despite that, some of them are fun.

Watchhouse Sergeant Phil "Filthy" Worth is a petty plodder who worries about his vans and his prisoners' meals. He's played with considerable ease by John Leigh. And public-counter sergeant Arthur Teleafava is the nice guy who just wants to help.

Put him in the interview room and he'll start talking about himself. He could make the toughest crook squeal - through boredom. Played by Brian Sagala, he's a delight.

But it's the larger characters, the flash cops, the detectives, who really plod their way through a script which, last week, really was a stinker.