Paul Thomas: We've got the political dirt you want in Sam Spades

The day was winding down. Somewhere in the world (Honolulu, since you ask) the cocktail hour was under way.

It was that time of day when a man's thoughts turn to the bottle of Old McStingy's single malt in the bottom drawer. Time to knock off and start working on tomorrow's hangover.

There was a knock on the frosted glass door bearing the words Dirk Quest, Private Investigator. I was christened Vere Lavender but names are important in this business. My brother Crispin tells me it's the same in interior design.

My visitor was a dumpy citizen in an ill-fitting suit. Going by the wild gleam in his eye, he'd either had four lines of Peruvian marching powder for afternoon tea or escaped from a padded cell. Either way, he'd fit right in with the rest of my clientele.

He introduced himself as Neville Glump Junior, snapped open a black plastic briefcase and extracted a folder which he slid across my desk.

"The people I represent want to know everything there is to know about this person," he said. "Follow him night and day, watch his every move, go through his rubbish."

The gleam cranked up to high-beam. That usually meant they were about to reveal they played chess with God every second Tuesday. "Leave no stone unturned."

"Who is he?" I asked.

"The very spawn of the devil," spat Glump.

I wiped his saliva off my forehead and opened the folder. The face in the black and white photograph was familiar but I don't keep up with the news since my TV set was repossessed. "He looks like a Rotarian."

Glump shook his head pityingly. "The greatest trick the devil ever pulled was to convince the world he doesn't exist."

It was a line from a film but somehow I didn't pick Glump as a movie fan.

A week later I rang Glump to give him a progress report. He and his associates wanted it from the horse's mouth. He gave me an address in Mt Roskill. Mt Roskill, I thought; there's a surprise.

The sign outside said Glump & Sons: Manufacturers of Christian Underwear. Glump led me through to an office where a crew of lookalikes were sitting around a table.

"I'm Neville Glump Senior," said the one in the middle. "There are my associates: Wayne Glump, Kevin Glump, Morris Glump, Horace Glump."

"I get the picture," I said. "The family that makes knickers together, sticks together."

There was a protracted silence, punctuated only by the sound of Glump Senior plunging a letter-opener into what looked like a Helen Clark doll. Eventually he said, "I understand you have some information for us."

I dumped a pile of crumpled, food-stained documents on the table.

"I went through the subject's rubbish as instructed. Seeing it doesn't involve endangered species, I presume you're not interested in what he has for dinner so I'll get down to the nitty-gritty: we have OECD reports, polling figures, focus group reports, Lotto tickets."

"That's the nitty-gritty?" snapped Glump Senior.

"I take it you're not into delayed gratification." I waved a loose-leaf binder. "You're not the only ones digging for dirt - this is a private investigator's report on John Key." I shrugged. "He's so vanilla it's scary. Our subject, on the other hand ... "

I showed them the love letters; even after a few days at the bottom of a wheelie-bin they smelled like Catherine Zeta-Jones' ensuite. "Note the lip-stick imprints; note the Business Roundtable letterhead."

I cleared my throat and put on a voice of breathless adoration. "Donny dearest, okay, I'm convinced - you really were named after Don Juan. And next time someone mocks your comb-over, just remember it makes my heart go pitty-pat."

Glump Senior lurched to his feet.

"What going on here?" he bellowed. "Just who have you been investigating?"

"Don Brash," I said. "That was the brief from Neville Junior."

Glump loomed over his cowering son. "You imbecile. Brash is the lesser of two evils; it's this godless Government we're trying to get rid of. We wanted dirt on that woman's so-called husband."

"I'm sorry, father," babbled Neville Junior. "I got confused. It's so hard to keep track of who's who when you can't watch TV or read the paper ."

"Give him a break," I said. "A couple of geeks with PhDs, it's an easy mistake to make."

The Big Glump turned back to me and uttered the words they'll engrave on my tombstone. "Quest, you're fired."

It was getting dark by the time I got back to my office. Somewhere else in the world the cocktail hour was under way.

A bloke with an obvious false beard and a hat pulled down to his eyebrows was waiting for me. "Mr Quest? My name's Theodore Muscovy. My associates were wondering if you'd be willing to undertake some inquiries of a sensitive nature."

"Muscovy, eh?" I said. "A duck by any other name would quack as loud."

I unlocked my office and ushered him in. "Care for a dram?"