It was somehow inevitable that Nina Conti would merge as one with her foul-mouthed simian sidekick, Monkey. While she prepared for her innovative new ventriloquism show for this year's Fringe, we asked what levels of meta-comedy this fresh hour will take us into and just how rude her chimp chum can get.

What's the premise of the new show and is it an idea you've been working towards for a while now?
I've loved the thrill of and challenge of improvising with audience members in masks; it feels like the gift that keeps on giving (and I do it in this show). God forbid Monkey should be out-shone so he's been to the Star Wars creatures department and given a major upgrade that liberates him from the limitations of being on my hand. But now he's living with a woman inside him dying of heat exhaustion so he may never be truly free. It's taken the relationship to a new level of unwelcome intimacy. And ventriloquism to disgusting levels of meta. But man, do I have fun in that suit!

When we hear about a ventriloquist being taken over by the 'dummy', it's hard not to think about Michael Redgrave in Dead of Night or Anthony Hopkins in Magic. What can you say to reassure us that you're ok?
Can't reassure you of anything. I'm not about to murder anyone, but my brain is splintered and the voices are getting louder.

Is working strictly to a script something that makes you feel unhappy?
Strangely, now that I've been off-script so long there's something about saying things that have been written in advance that makes me feel dishonest. Like when you're in a conversation with someone and you can tell they've prepped what they wanted to say to you, it can feel like you've been left out of the equation. I know that's ridiculous in a show context, with all the great plays and written stand-up that exists, but it's hard for me to shake that feeling. My favourite thing is to create a shared and unrepeatable experience out of what is in the room for one particular hour in time.

What's the most inappropriate thing to have come out of Monkey's mouth?
That can't go in print: it's about the most disgusting thing you can think of and it left me blushing and wanting to leave the stage because I was so committed to allowing him to be free of censorship.

What do you love most about Monkey and what gets on your goat about him?
I love that he has no accountability and I'm envious of his position of not being real. Being a real person is quite a slavish experience. Don't think I have a goat.

Nina Conti Is Monkey, Underbelly Bristo Square, 1–27 August.