Kim Noble

is a performer who inspires contradictory responses. At the end of his most recent solo show,

You’re Not Alone

, for instance, I was not sure whether I wanted to hug him or perform some kind of citizen’s arrest. The show is nakedly autobiographical: he invites his audience to witness the bizarre minutiae of his life, from hilariously gauche comic interventions into the drab world around him – mocking up a B&Q uniform and unhelpfully assisting customers, practising very amateur taxidermy skills on a dead pigeon – to the utter horror of his struggle with severe depression.

With a background in fine arts and stand-up comedy (he was one half of the Perrier-award winning Noble and Silver), Noble’s work in the theatre is a blend of contemporary performance, comedy and video, where nothing seems to be off limits. He drills holes in his wall to record his neighbours’ sex life (which he charts), develops a stalker-like obsession with his local supermarket cashier, defecates in a church and goads anonymous sex pests online by pretending to be a woman who will indulge their fantasies.

Together with images of Noble’s ailing family members, they are all drawn into his startling and provocative show without any obvious consent. It’s a riveting, unethical piece, one you often watch through splayed fingers, with a twist in your conscience.

Noble can be similarly contradictory in person. On stage he is deadpan in delivery and can seem inscrutable, unsettling. “I’ve been told that,” he says, today sounding meek as a lamb. “I think I’m actually quite a nice bloke. So it’s kind of weird that there is this other thing that people see.”

Simon the pet maggot

On the morning we speak, he is bringing his new pet maggot – rescued from a recent infestation in his house and provisionally named Simon – to a public library in London to document what happens. It’s not untypical of his many projects, but Noble sounds delicate.

“You’ve phoned on a bit of a bleak morning,” he tells me, and apologises if he seems all over the place. “I was just in a bit of a mess and then somebody came up to me and said something really sweet, so that’s quite a nice thing to happen in central London.”

Noble's work isn't immune to the kindness of strangers: in You're Not Alone his obsession with Keith, a checkout attendant he films surreptitiously, comes from some sort of affinity. The people in this contemporary picaresque are all tiny entities in a vast, impersonal space. "It's the cashier who you don't spend much time noticing, or the local Indian takeaway guy, those kind of people as well, rather than just me, I hope: small, little people, me included, in this kind of metropolis trying desperately to get by somehow."

Noble’s war against anomie is usually hilarious. Having “worked” undetected for some time in B&Q, he requests a leaving party when he decides to stop. But his fascination with grimmer scenes brings him into risky territory. Finding some graffiti in a motorway station toilet one day, with a mobile number seeking pictures of customer’s wives, he enters into a long, artless correspondence with a lorry driver, furnishing him with creatively faked images of female genitalia. Later, he becomes Sarah, perhaps the least convincing drag persona ever created – then begins to meet men for profoundly awkward encounters in hotels.

But it’s not all guerrilla performance. Elsewhere we see Noble bathing his demented father; a shot of his alcoholic brother passed out on the floor; and Noble himself crying uncontrollably in a bout of depression.

Issue of consent

I ask about the ethics of involving other people in the show and whether anyone consented to have their images used. (When Noble's previous show, Kim Noble Will Die, provided audiences with his ex-girlfriend's phone number and encouraged them to send abusive texts, she threatened to sue.) "Um, so," he hesitates. "I might have to be slightly guarded. No, the consent issue is a very tricky, awkward one."

A supermarket gave its consent for him to film on its premises, for instance, but Noble was less than honest about his intentions. “Generally these people aren’t aware what’s happening,” he says. Were these deserving targets, you might feel more comfortable with Noble’s intrusions, but as a satirist he generally goes after small fry rather than big game.

“Yeah, it’s ridiculous. Getting arrested in Ikea isn’t necessarily close to taking down a big corporation,” he says. A lot of Noble’s drives seem to mystify even him. But, he says, he’s never trying to harm or insult anyone. “It’s kind of done with a ridiculous twist on it.”

He will find himself following Keith home, meeting a stranger disguised as a woman, or recording the neighbours, and say to himself, “What the hell am I doing?” In Noble’s work, which is nearly always a creative document of his life, this seems to be a frequently asked question.

“It is also done with a slight madness,” he says. “The whole thing is a bit insane. But, I suppose, I feel a bit insane.”

Noble's mental health is a source of much of his humour, but it's no joke. He battles with manic depression, and, when performing Kim Noble Will Die, threatened suicide during the performance. A psychiatrist accused the theatre of being irresponsible for letting Noble perform it. Now Noble performs on condition that counselling is provided.

Otherwise, the work that provides him some necessary stability. “I don’t have a proper job. I don’t have a proper life. Documenting stuff is what I’ve been doing for the past 10 years, really. Just recording things. That came through a sort of madness. Also it did fit a sense of: maybe I can remove myself from it if I document it? If that makes sense?”

Did it also make him inclined to live his life as a sort of performance, taking an idea as far as possible because there is always an audience potentially in mind? “I don’t see a lot of difference between them,” he says of his life and his performance. He is especially bothered when people think everything in the show is an act. “The place it comes from – the loneliness, the isolation – isn’t made up.”

The threat of chaos

It would be too glib to consider Noble’s practice a form of self-help, but his countless projects, and the show itself, give him a useful structure against the threat of chaos. “Aw, man, massively. Someone said that I needed these projects to keep my gnashers down; I needed to gnaw on these things to survive. It definitely gives me a purpose in life at the moment, I suppose.”

There’s a risk on both Noble and the audience’s part to conflate the man with the performance: for Noble, because rejection of the work feels like a verdict on his life; for the audience, because there is a considerable and daring artistry to what he does.

It’s not always easy to say what is satire and what is symptom in this outrageous picture of modern disconnection, but Noble affectingly captures its unease. Those who love him for it are not alone.

What did the consoling London stranger tell him, in a moment of crisis? “They said, ‘Sorry to be that weird stranger stopping you in the street. I really like your work. Keep going with it.’ ”

• You're Not Alone runs September 16th-19th in the Peacock Theatre as part of the Tiger Dublin Fringe