Being the only high-profile female ventriloquist in Britain, Nina Conti is used to sticking out a mile whenever she appears on a comedy bill. But in early June, she had the odd experience of playing second fiddle during a gig at London’s Backstage Comedy Club, the venue for the stand-up debut of Lib-Dem politician, and former Cheeky Girl lover, Lembit öpik. ‘There was such a build-up to it, but for a first gig, he was extremely proficient and quite witty. It was an impossible one for him to play because it was such an unnatural audience, full of press and PR. There were about a million jokes at Lembit’s expense popping into my head but it would have been a bit tacky to make them.’ A pause, then a sly grin. ‘Well, I did make one.’

That bizarre night capped an eventful couple of years for Conti (daughter of Tom) during which she has made a documentary feature about a US ventriloquist convention and performed at the funeral for actor and impresario Ken Campbell, the man who first suggested to her that sticking a hand up the back of a puppet was the way forward for her career. Initially reluctant to heed his advice, Conti is now for ever in his debt.

Campbell also bequeathed his own army of dummies and dolls to her and she took them on the road as part of the documentary, entitled Her Master’s Voice. ‘There’s this place in Kentucky which is a mausoleum for puppets of dead ventriloquists, so I took Ken’s puppets on a trip there. He also left me a puppet of himself so there was the trickiness of trying to find his voice with him gone; all the puppets were bereaved, as was I, and they had to find new voices.’

For Talk to the Hand, her third full Fringe run, Conti is set to try something a little bit different. In collaboration with Bill Dare, the producer of Spitting Image, she has conceived a chat-show format, which allows for more of an improvised set-up as she and the puppets can shoot the breeze with any guests who drop by and an audience. ‘It’s a bit more frightening as there are more characters but also more unknown variables. I’ve been sticking to a scripted act for so long and this one provides areas for going off on one, but I find it exciting and often funnier because you know it’s genuine. I do often get hysterical to the point where the puppet can’t talk; it’s a giggly place to put my brain into.’

While Conti finds the whole ‘vent’ thing a good old laugh and there’s ongoing talk of a sitcom called One Free Hand with the involvement of Conti, Armando Iannucci and Peep Show writers Sam Bain and Jesse Armstrong, there remains something of a chauvinistic attitude to the genre within certain comedy circles. Daniel Kitson once advised her to chuck the puppets away and be herself, and the fact that Conti is one of only three bona fide ventriloquist acts this Fringe (Paul Zerdin is revisiting his Sponge Fest while David Strassman and Chuck Wood are making a long-awaited return for Duality) perhaps suggests just how extreme a niche it remains.

‘Is it because it’s seen as just talking to dolls?’ Conti wonders out loud. ‘But then we all thought the Muppets were cool. Having met some of the really good ones in America, it’s so solid and self-aware. There are one or two who take it a bit seriously and are a bit strange but I didn’t meet them. I heard this story of a ventriloquist act who was so bad that the audience just started laughing. When he left the stage, he really berated the puppet and threw it into the suitcase, walked out the door and was never seen again.’

So have you ever felt an urge to blame your tools? ‘There was one new puppet who I was struggling to find a voice for. I would look over at it and think, “You’re totally letting the show down, you stupid latex thing. Pull your weight”.’

Nina Conti, Pleasance Dome, 556 6550, 7–30 Aug (not 16, 23), 8.30pm, £12–£13 (£10.50–£11.50). Previews until 6 Aug, £6.