It’s 11 am, on Friday, May 15. BBC Television Centre. A rehearsal room.

First read-through for series two of The Thick of It. It is a perfectly nondescript conference room – table, chairs, faint odour of hot dust – until you walk halfway in: at which point, you realise it overlooks the Blue Peter garden.

As each cast member of The Thick of It arrives, their greetings (“Morning!” “Bonjour, c***y-b******s!”) are abandoned in a flurry of Proustian squealing (“Oh God! The Blue Peter garden! Didn’t they bury Shep there?” “I knew someone who said he knew the boys who vandalised it.” “So did I.” “Oh, that’s a bit suspicious. Someone must have been lying.”)

Peter Capaldi – who plays spin doctor Malcolm Tucker: the boiling man-kettle who ends phone calls with “F***ety-bye” – is tired-eyed and bearded, and staring down into the legendary location.

“They always used to say it was a garden for the boys and girls of Britain who didn’t have one,” he muses. “But you can’t help but notice its modest size would have made that, ultimately, quite impractical.”

Today is the first read-through for what is, officially, Draft Four, Episode Three, Season Two of The Thick of It: the BBC political sitcom that looks like a documentary, stings like a bee.

It’s been recently voted the 19th Most Admired programme of all time, won two Comedy Awards and two Baftas – one for Best Situation Comedy – and is required viewing on Fleet Street and in Westminster.

A couple of weeks ago, I bumped into a Shadow Secretary of State at a party. “Pretty much every day, at some point in the office we will say, ‘This is like The Thick of It,’” he sighed.

Thick has – like Spitting Image before it, although using a wildly differing methodology – given most people in Britain a better understanding of the political system than 1,000 hours of Newsnight. And in Tucker – the New Labour spin doctor obviously based on the equally vituperative Alastair Campbell – the show has a character who sits in the same sitcom pantheon of legends as Basil Fawlty.

Pound for pound, it must have the highest ratio of critical acclaim to running time of any sitcom since Fawlty Towers. For, since its inception in 2005, the entire canon of The Thick of It consists of six half-hour episodes and two hour-long specials. Barely an evening’s worth. You couldn’t get halfway through a transatlantic flight to LA on the boxed set.

That it’s made so great an impact with so little physical presence is primarily down to one man: Armando Iannucci, the show’s creator, writer and producer. Jesuit-raised, Oxford-educated and producing Week Ending on Radio 4 by the age of 26, Iannucci has brought three big shows into being – The Day Today, I’m Alan Partridge and now Thick – all of which are certainly among the top five comedy shows of the past 15 years, if not simply comprising the actual top three.

For aside from being very funny himself, with a clear-eyed moral viewpoint, Iannucci’s greatest talent is for making teams of people want to be as brilliant as they possibly can.

Editor's choice

• The 100 Best Films of the Decade
• 70 facts you didn't know about Marvel
• The 50 Biggest Movies Of 2010