The announcer at the end blows a big raspberry at those "who didn't enjoy" Two Episodes of Mash. Well, that includes me. Supposedly a surreal sketch show, it's certainly weird, in that it fails to deliver a comedic punch on almost every level.

Tame tales of an app spewing lava, a stripper's trousers and animals entering the Ark are intercut with a flabby running gag about protagonists Diane Morgan and Joe Wilkinson settling into the studios of Radio 4.

To be fair, the libidinous snooker referee idea had promise, and I get what they're trying to do. If you like wacky played as mundane this could be for you.

This is gentle, absurdist, mini-sketch comedy, piloted in Radio 2 then given a series there back last autumn. These four new episodes come with a significant additional element, an animated trailer. To watch this go to bbc.co.uk/radio4. It's short, sweet and matches the humour of the show, the work of clever young artist Tom Rourke. But why is radio promoting itself visually? Because that's what reaches a generation who use smartphones to access everything, train times to pizza offers, with radio somewhere in the middle. The visualisation of radio is a growing field, increasingly used by commercial operators (to match advertisers to audience) as well as the BBC (always anxious to catch new listeners in any corner of their net). What matters still, however, is programme calibre. I think you'll find it here, in the company of Diane Morgan, Joe Wilkinson and David O'Doherty.

A very funny and understated comedy show starring Diane Morgan and Joe Wilkinson, the kind you don't expect on Radio 2 but all the more welcome for it. I reviewed its first show (glowingly) three weeks ago. This is its last. It richly deserves to come back. The only question is where? Radio 2 is losing lumps from its comedy budget and on Radio 4 they mostly go for comedy that SHOUTS at you. Fingers crossed.

Budget-related cuts are squeezing comedy on Radio 2. The plan is to "move away from built comedy slots" to "ad hoc" series across the year, including decommissioning The Comedy Hour on Saturday evenings. Last Saturday evening's slot contained Two Episodes of Mash, an offbeat, surreal and occasionally hilarious sketch show from Diane Morgan, a kind of depressive female Larry David with a deadpan Lancashire accent, and Joe Wilkinson. It's the prerogative of sketch shows to be inconsistently funny, and having laughed out throughout the second episode, the third was a little downbeat, but given that downbeat is the signature mood of the show, it seems wrong to complain. The pleasure of the series is the way sketches merge seamlessly into each other, so one moment it's a pair of lobsters in a restaurant tank, "I feel trapped, I'm hyperventilating. Why she's pointing at me?" and then it's a tarot reader with football cards. "The John Fashanu card means at some point you will become invisible. Gordon Strachan - your hair's prone to matting and you may become dormant." A striking thing about this show, and so unusual for topical comedy, is that the sketches are entirely detached from the news agenda and none the worse for it.

Do not, if at all possible, miss the final part of Two Episodes of Mash (Radio 2, Saturday night). This is a very funny, inventive and engaging comedy show, written and performed by Diane Morgan and Joe Wilson. It is also quiet (no studio audience) and therefore intimate, welcoming you into its various fantasy worlds where a sheepdog colludes with a sheep and a queen bee finds out what's really happening in her hive from a wasp who's joined for the fringe benefits.

The overall impression is shambolic, but don't let that fool you: the moments of silence, lapses in concentration and misplaced judgements of taste are cleverly scripted comedic tools that give this highly professional duo - Diane Morgan and Joe Wilkinson - the air of amateurs. Bored, fed-up and rather grumpy amateurs at that.

Once more, the sketches where they pretend to be animals are the funniest but there are also glimpses of surreal genius - blowing the programme budget on an ice sculpture of Tim Henman, for example - that make this worth a try.

Ken Bruce is the overlord of Radio 2 and he's been running a tight ship. So, when young comedians Diane Morgan and Joe Wilkinson asked his permission to broadcast their sketch series he laid down some strict conditions. Hear the wrath of Bruce here as the duo fail to provide him with the introductory theme tune he's demanded. Around this frankly strange set-up, comes a string of equally surreal sketches, the best of which involves two spiders discussing what it's like to be caught under a glass.

After a successful pilot episode last year, the kooky sketch show Two Episodes of Mash (Radio 2, 10.00pm) returns for a four-part series. Starring Diane Morgan and Joe Wilkinson, it begins by wondering what Rapunzel would have done with an intercom, and what spiders think about when they're trapped under a glass.

Admit it. The continuity announcer says, "And now, award-winning comedy from last year's Edinburgh Fringe..." and your finger and thumb go into instant retune. Experience has shown that mere seconds may now stand between you and a verbal avalanche of copulation, defecation and general tribulation.

Experience, however, is not an infallible teacher. Had I heeded it I would have missed Two Episodes of Mash (Radio 2, Saturday) and this, the seventh of eight Comedy Showcase pilots, was quite wonderfully funny. Better still, it was brilliant radio. A queen bee conversed with a wasp who knew everything going on in her hive, Peter Pan and Tinkerbell talked about old times in a Peterborough supermarket, a fortune teller used a tarot pack made from footballer cards, we heard what it's really like at the end of the rainbow. It was comedy that leaves you seeing everything its way (as Hancock did, or Monty Python). Diane Morgan and Joe Wilkinson, its makers, may bear the stigma of being Edinburgh Fringe stars but if Radio 2 doesn't sign them up instantly I'd like to know where they're working so I can buy tickets.