The best sitcom on radio? John Finnemore's series about the four staff on a one-plane, tinpot charter airline - and it's just as silly and as tightly constructed as ever in its fourth run. Roger Allam stars as suave, incredibly untrustworthy first officer Douglas, with classy support from Stephanie Cole, Benedict Cumberbatch and Finnemore himself.

Light relief in the dreary first full working week of the year came from the return of Cabin Pressure to Radio 4. One of the station's few contemporary sitcom successes (more on that subject another week), it has lured Benedict Cumberbatch and Roger Allam back for a fourth run at playing odd-couple pilots Martin and Douglas. The pair man MJN Air: a tinpot, one-plane budget airline owned by middle-aged divorcee Carolyn, played by Stephanie Cole. It's an impressive cast - Allam does a great line in supercilious grumps and he is in his element as the snarky first officer to Cumberbatch's prissy, uptight captain. But perhaps the real star of the show is its writer John Finnemore, who also plays Carolyn's doofus air-steward son, Arthur.

"The code red is there to stop me being too helpful, and I can't stop being too helpful by being more helpful," he bumbled at his mum, in a script packed tight with superb lines. The crew had assembled for Birling Day, the annual jolly enjoyed by their stupidly rich (and often drunk) regular customer, who charters a flight each year to take him to see the Six Nations rugby final. Except this year, the match was taking place at Twickenham, a short drive from Birling's own house. No matter.

After a row with his wife and in a fit of pique, Birling ordered a trip to watch the match in Timbuktu. Miles of daft behaviour followed, the highlight being Allam's smug laugh - "Madame is a humourist?" - as Douglas bartered with Carolyn over a bottle of whisky.

John Finnemore: Timbuktu episode blog

John Finnemore explains the thinking behind the 'Timbuktu' Birling Day linked episode of Cabin Pressure.

John Finnemore: radio, comedy & Benedict Cumberbatch

We talk to the creator of one of Radio 4's funniest sitcoms about the new fourth series, and the show's unbelievably starry cast.

Hurray! Here's the fourth series of John Finnemore's splendid comedy made magical by the brilliance of its cast. Stephanie Cole plays Carolyn Knapp-Shappey, formidable owner of a one-plane airline. Benedict Cumberbatch is the sole Captain, Roger Allam as First Officer provides a one-man masterclass in timing and Finnemore himself plays the owner's cheerfully hapless son. There's enough here to banish the New Year blues, even if your electricity bill just arrived.

Cabin Pressure IV - prepare for boarding

Bing bong. I have Cabin Pressure news. Yes, actual news! Not just news about when we hope to know when we might get news, but the news itself. All of it. Are you ready? Ok. Here is the news.

The hairline of Captain Martin Crieff

So, I've been getting some emails... As far as I remember, Martin's hair has never been mentioned on air.

Cabin Pressure update

Though we still haven't got the dates totally nailed down, it's looking increasingly likely we'll be recording Series 4 before the end of the year.

Cabin Pressure FAQ

I've been getting a few questions about Cabin Pressure recently and I thought I'd put the answers to as many of them as I can think of here.

John Finnemore: blog about St Petersburg episode

Well, I thought it was about time I did an exciting final episode. Both the final episodes of the first two series were 'shut-in' ones...