I guess by now Rosa Robson and Matilda Wnek should be a pretty fluent pair, but it’s a little unnerving how smoothly they come across. Over the course of the interview, a clear pattern emerges – Rosa begins their answer, Matilda will interject and intensely, at vertiginous speed unpack the substance, and Rosa will sum it up with a joke and a smile. That their words are overlapping, endearing, and occasionally nonsensical, speaks volumes of a duo who aren’t afraid to take silliness seriously.

I meet them on their return from the Edinburgh Fringe festival, where they performed Beard, their two woman, one pianist (an absent Stephen Bermingham) show. They’re each adamant it’s not like regular Cambridge sketch shows – “Beard has a very clear idea of its sense of humour, it’s self-aware, playful, surreal” Matilda says. Structurally, it’s different too: the sketches are spliced together with snippets from a TV channel called, surprisingly, Beard.

This is where Bermingham comes to the fore: Stephen is the voice of Beard TV. He’s worked before with The Scat Pack, amongst many other vaguely theatrical ventures, and they see him as the rock of their show – an anchor at the back, staying seated and calm whilst they run themselves into exhaustion on stage. Whilst in conversation they barely pause for breath, on the stage there’s less running around these days, as the show has become less frenetic with time. Part of that’s a response to audience feedback – they can’t speak highly enough of the gift of the “autonomous critic” that getting bums on seats provides – which means they’re taking more time with their material. They had an epiphany very early on in their performance run: Matilda finally let a close friend of hers see it, and their favourite jokes fell completely flat. So what went wrong? “We skipped a step,” Rosa says. The set-ups weren’t easily discernible – “there’s a lesson to all sketch writers out there,” Matilda interjects – “half the battle is making yourself clear.” After that, they went through the show, put in the set-ups, and, according to Matilda “it just flew, it was great.”

They’ve gradually been putting a stop to some of the misunderstandings that two women playing over one hundred and fifty characters can engender. They recall Rosa’s dad coming to see it one night, and being a little bemused by his reaction. He said, a little uncomfortably, that there were a lot of lesbian encounters in the show – though they weren’t aware of any. It’s to this end, after every show they’d have some noodles and work on clarifying the sketches – “thinking it through, being like ‘oh, now we know that’s a woman!’”. They recall being obsessively attentive to the show in Edinburgh – “it was like a drug. A fun drug. We didn’t really go out in Edinburgh, we were just spending time with the show, writing and re-writing bits. We were very antisocial.”It feels like they’re putting in the work so the punters don’t have to. Certainly, I get the impression that their brand of comedy is otherwise remarkably laid-back – Rosa says of the audience “we don’t want them to have to do any work, we want them to come in, to enjoy it and have fun.” There’s an eagerness to please in the way they speak, something that echoes with some of their performance experiences at the Fringe. Matilda, who has been the more forthright of the pair, recalls with a blush the first time they had kids in the front row – “I felt uncomfortable and so I changed the script so that there were no swear words.” Rosa too, confesses to coughing over a particularly choice expletive when her Grandma came to see the show.

I’m a little sceptical of such a malleable approach, but they say they’re over that now, seasoned by a month of performing to an Edinburgh audience of all shapes and sizes. Their sensibility is also part of their appeal: they make it clear how grateful they are for all the help they received in Edinburgh, and there’s no hint of disingenuousness when they speak of how excited they are to be performing it twice more, to their home crowd. The excitement extends to the new intake of freshers; they’re over-brimming with advice to wannabe comedians. Matilda is the membership secretary for the Footlights Committee, and she urges those with a comedy bent to “audition for every smoker. I cannot express that enough. You’ll always learn from it and you’ll get better.” Rosa adds – “Don’t be afraid to venture out on your own, grab a group of like-minded people and give it a go.” It’s an admirable attitude.

With Beard, Rosa and Matilda seem to want to work together on a different approach to comedy – more slapstick, more surreal. It sounds pretty fun.

Beard is on at the ADC at 11pm on Thursday 18th and Saturday 20th October