We left our two eponyms in a thoroughly bad place at the end of last week’s episode: they were arguing angrily and worriedly about Stacey not having been on the pill for a year in the hope of speeding up their chances of getting pregnant. Things are really no better this week for them, unfortunately, with a fertility doctor revealing to them that it’s Gavin’s low sperm count that’s been standing in the way of them conceiving all this time.

Writers Ruth Jones and James Corden are fantastic when it comes to giving enough attention to the poignant scenes among the more farcical ones – something I think sets this comedy drama well apart from a lot of silly tat posing as comedy on the BBC. The scene in which Gavin and Stacey drove up to Essex immediately after the appointment was very moving, with the two characters utterly strained and unable to talk, but offering just a glance or a hand-squeeze in support of each other.

Of course, the couple might have preferred to stay in Barry and have some quiet time by themselves to absorb the upsetting news, but they were required in Essex for Dawn and Pete’s wedding vow renewal ceremony. Everyone went grudgingly to the rather pointless event, but in the end it turned out to be much enjoyed by all, particularly Smithy who managed to have a double-whammy of triumphant moments. Firstly by walking Dawny down the aisle, then by putting Dave Coaches very much in his place in revealing his curry night antics with Nessa.

Hopefully this signals the beginning of the demise of Dave Coaches. He is a continuous irritation for everyone, including his fiancée. He made a right baggage of himself in this episode, by being an obnoxious backstreet driver in Bryn’s car, then by attempting to drag Nessa and Neil the baby away from the renewal before Smithy had managed to spend any quality time with his son. He’s absolutely got to go.

As ever, the small and quick-fire details in the writing were the real treasure: Pete and Bryn have apparently become online friends on Facebook and Twitter; Pamela watches the film Doubt but names the star actor as Philip Dustin Hoffman instead of Philip Seymour Hoffman, as we all might well do in an absent-minded moment; Pamela thinks the expression is “ours is not to question while” which Mick decides is incorrect but makes some sort of sense; Dawn asserts “we’re only renewing our vows; we’re not Louise and Jamie Redknapp.” It’s absolutely these small, natural elements peppered into the script that make the world of the show so familiar and charming.

Not very many episodes left, then, for Gavin and Stacey to make some sort of progress in their longing to have a baby, and for Nessa to realise that Smithy could and should be her man. Whatever the conclusion at the end of the series, I think we can feel assured that Corden and Jones will take us there with the brilliant mix of sharpness and softness that’s characterised their work so far.

Read our review of episode 3 here.