Gavin and Stacey have moved back to Barry, and the Shipman family cohort is heading down the M4 for Neil the baby's christening. It's a mixture of warm, toasty moments and crass comic set pieces in lieu of gags. Between Jones and Corden you can guess who wrote which bit. Tedious phone business with Smithy and Gavin repeatedly calling each other "slaaaags" - probably Corden. Sweet exchange between Stacey and her mum: "Ooh, I just called you Gwen!" - most likely Jones. It's still nice, but it has an extra edge of cynicism since the Horne/Corden toxic media assault of 2009. Rob Brydon steals the episode as usual, though.

Where Little Britain produced bizarre, gross-out comedy, Gavin & Stacey is a very traditional sitcom. It works in the manner of Dad's Army or Birds of a Feather - the eponymous leads, played by Mathew Horne and Joanna Page, provide a focus in front of a background populated by slightly grotesque caricatures, such as Rob Brydon's camp and simple-minded Uncle Bryn. Now for this third and final series, James Corden's Smithy is still living in Essex while Gavin (his best friend) and Stacey (Gavin's wife) have moved to Stacey's home town of Barry Island in South Wales. As the familiar characters reunite for the christening of Smithy and Nessa's son Neil, viewers who are new to the series (which has previously won two Baftas) may find that this opening instalment is not as immediately likeable or accessible as they might wish. Who, after all, would choose to spend time in the company of Gavin's shouty mother Pam (Alison Steadman) or Stacey's offensive best friend Nessa (Corden's co-writer Ruth Jones)? But as this first episode continues (next week's second is much funnier), it becomes obvious that these weirdly dysfunctional families makes a kind of sense - and that their ludicrous travails are no more ludicrous than most family's. So it's all very sweet, even if there's none of the innovation or edginess you'd find in The Office or The Thick of It.

By his own admission, Keith Barret is not a natural performer and his interactions with the audience here combine crashing naivety with staggering social ineptitude. Yet this routine, "an uplifting chat about marriage" - as delivered by Rob Brydon - is both hilarious and heartbreaking. Brydon first sketched Barret in the wonderful Marion and Geoff monologues and, in this show from 2005, he's drawn a fully three-dimensional character. Sandwiched between two routines from host Jack Dee, Brydon is outstanding.

By chance, John Humphrys asking "Would you like a turn?" featured as one of the Questions That Are Never Asked on the new series of I'm Sorry I Haven't a Clue. The choice of Jack Dee to take over from the lamented Humphrey Lyttleton was an inspired one, even if his first joke about Jacqui Smith's husband destroying her career "single-handed" did sound a lot like The News Quiz. Fortunately, with the help of panellists like Barry Cryer and Graeme Garden, the programme's unique flavour remains. Like Wogan's world, the "antidote to panel games" depends a lot on the surreal, the in-joke, and the trick of being risqué without being offensive. New games like Pensioners Film Club ("Death in Fenwicks" "The Postman Always Has to Knock Twice") mixed with old favourites like One Song to the Tune of Another. The sound of Rob Brydon singing the words of Jim'll Fix it to tune of "Mad World" made me choke with laughter. The problem with in-jokes though, is that people get them too quickly. At one point Jack Dee had to issue the howling audience with a plaintive reprimand. "I have got punch lines... please wait."

Gavin & Stacey's late developer Rob Brydon

He was rejected from RADA for being too provincial and told he had a face made for voice-overs (for toilet duck). How did Rob Brydon fight back? Two words: Uncle Bryn.

You need to watch QI. I don't know if you know it at all, it's been around for a while in England. Stephen Fry's the host, Alan Davies is the permanent guest star and there's a rotating panel of famous people whose qualification for being on is they're amusing. Or Quite Interesting, which is what QI stands for. It's really just people talking shit. Tonight they're Rob Brydon, Andy Hamilton and Charlie Higson. I only really know Rob Brydon, and I love him. He's in Gavin & Stacey at the moment, it was on UKTV last night, he plays Bryn, Stacey's uncle. The topics on QI are letters from the alphabet, we're up to the Fs at this point, a fair way into the series. But it's a loose half hour. Tonight includes James Bond's job, Mick Jagger's walk, Bert Ward's post-Batman and Robin career in porn, and flags. Quite a lot about flags - extremely entertaining and mindless, just what you need during stressful times of (insert source of personal worry here). Even the buzzers are good - Andy Hamilton's is the Captain Pugwash music.

Tonight's is another ludicrously enjoyable edition of the fib-based panel show that will, if you're not very careful, have you giggling like a schoolgirl throughout. Mind you, there's an uncharacteristic lapse early on when guest panellist Sir Chris Hoy makes a claim that even by the standards of this series is clatteringly implausible. Do we for a moment buy the idea that Sir Chris was approached by Nasa to cycle on the Moon? I mean, come on. After that, truth and lies become harder to separate as we mull over whether Gabby Logan wears red underwear when she presents a show for the first time and whether Lee Mack was force-fed custard creams at school. Host Rob Brydon is on sparkling form and David Mitchell is, you won't be surprised to hear, effortlessly funny. But was the only time he ever went to a live music concert a trip to see Shirley Bassey?

Rob Brydon Interview

Rob Brydon: "Lots of things, momentous things, happen. I can say Uncle Bryn is in it a lot, I think he has more to do than he has in previous series."

The best bit this week is David Mitchell's sort-of impression of Jodie Marsh (she's a "glamour model", the one who isn't Jordan). Of course Mitchell is ill-equipped even to approximate Ms Marsh's two famously overblown assets, but he does a very decent career precis of the big-bosomed one's raison d'etre, albeit delivered in his exasperated A-level history teacher's voice. It's pretty much down to captains Mitchell and Lee Mack to keep things going, with some lacklustre guests. Jimmy Carr is impossible to like; Terry Christian is clearly baffled and well aware that he's out of his depth, to the point that you might end up feeling sorry for him; and singer Jamelia yet again inexplicably turns up on a TV panel show. Host Rob Brydon helps the show bounce along as he referees the arguments and interrogations: was Christian interrogated by police hunting a jewel thief? And did comedian Marcus Brigstocke work as a podium dancer?

Would I Lie To You? Review

"I'm going to hate this aren't I?" bristled David Mitchell as new host Rob Brydon prepared to recite from the Cockney Bible. But raising the hackles of the amusing Mitchell is one of the conceits that Would I Lie To You? relies on to thrive and survive.