Over her 10-year standup career, Hannah Gadsby had played to more than a few thin midweek houses. So when she was making her 2017 show Nanette, and beginning to sense it might be rather good, the Australian comic dared to dream an impossible dream. “I remember thinking: ‘Wow, it would be great to be able to not worry about whether I’ll sell the room on a Wednesday.”

Reader: her dreams came true – and then some. Nanette, a disavowal of comedy (its lies and omissions, the damage it can do) disguised as a standup show, became one of the major entertainment events of the decade. It won the biggest prizes at the Melbourne and Edinburgh comedy festivals, toured the world, and its Netflix special became a cultural phenomenon, earning Gadsby a best writing award at last month’s Emmys. Far from worrying if anyone will show up, she now counts Emma Thompson and Monica Lewinsky among her many famous fans. “It really is mind-boggling what’s happened to me,” says Gadsby, mid-tour and cheerful on the phone from the US. “Literally my mind is boggling.” Then – never one to leave an imprecision hanging – she qualifies: “Actually that’s not literal: I don’t know what boggling means.”

The show she is touring is her first post-Nanette offering, entitled Douglas. It is playing to audiences far bigger than Gadsby had become used to (even the Wednesdays are selling), and will land in the UK this month. As we shall see, it’s a reaction to the furore around its predecessor, as well as a placeholder while Gadsby calculates what to do with her new status. She has not adjusted to it yet – her life has changed beyond recognition – and is still puzzling over what made Nanette so profound an experience for so many.

“As I toured Nanette,” she reflects, “the #MeToo movement hit its straps. There was a zeitgeist that made it blow up like it did.” Nanette was about Gadsby’s sometimes brutal experiences of sexism and homophobia, particularly in her native Tasmania. With meticulous control, it spoke about how she turned those experiences into jokes – and, by doing so, collaborated in her own oppression. At least to begin with, it didn’t stint on classic one-liners (“I’m not lesbian enough … I mean, I keep my hand in”) but it repurposed them to radical effect (“I wouldn’t want to be a straight white man if you paid me, although the pay would be substantially better”). Then – bait-and-switch successfully accomplished – it set the gags aside, and instead delivered a savage critique of how comedy works and which stories it will and won’t let us tell.

Hannah Gadsby performing Nanette. Photograph: Ben King/Netflix

That may be why, Gadsby speculates, a lot of people “who don’t feel catered for by standup as it has usually been” flocked to her show. “But also,” she admits, wrestling with the reasons for Nanette’s impact, “I have no idea. I could give you a lot of theories. I put a lot of work into that show. It’s not an accidental piece of work. But I wouldn’t be able to tell you what the recipe was that made it land like it did.”

If the explanation is elusive, there is no doubt about the show’s transformative effect on the 41-year-old’s life. Gadsby was a respected fringe-festival regular. Her style was downbeat bordering on dour, with the low energy redeemed by forensic wit (often at her own expense) and the kind of heavy sardonicism signalled by 2011’s show title Mrs Chuckles. It all added up to a credible – if not lucrative – standup career: until Nanette, she “didn’t believe I’d ever be able to afford a home of my own”.

The show’s success put the kibosh on Gadsby’s plan to retire from standup. She made the “I quit” announcement onstage as part of the show; it was a key part of Nanette’s excoriating effect. Now, she reclassifies that as a theatrical device. “It became this very odd mix of a conceit and also: ‘I mean it.’ What it meant was: ‘I don’t care about my reputation as a comedian. I don’t care about the artform of comedy. I care more about what I’m saying, not how I am saying it.’ But it became cathartic for me to say it onstage and kind of believe it.” She pauses, then – as if she needs to justify still being a comedian – adds: “but also: what am I going to do? Sit on a park bench? I can’t quit. I’ve no other skill set.”

So here she still is, a full-time, gigging comedian, albeit one whose sense of herself has changed dramatically. “Before Nanette,” she says, “I didn’t feel like a powerful person at all. I was always very low status. And now I have high status. I have a platform, and a lot of people will read or listen to what I say. I am not, as an individual, oppressed any more,” she says, the amazement audible in her voice. “But I still represent a collection of identities that are oppressed minorities.”

As an art history graduate (she has made shows on the subject; one of Nanette’s most pointed routines was about Picasso), it amuses Gadsby – a self-described “big queer woman from a low socio-economic background” – that her work is now canonical. “It’s really funny to me that if there’s a canon of comedy – which is not an idea I’m a fan of – then I’ve just sort of plopped myself in there.”

But the adjustment she is having to make is practical as well as conceptual. Her life is busier and harder to navigate now – which is not easy for a woman who has been vocal in the past about her social unease. “I am finding it hard,” she agrees, “because I like familiarity and there’s not much about my life just now that is familiar.”

Which brings us to Douglas, one of the standout themes of which is Gadsby’s autism. She was diagnosed as autistic just before she made Nanette. It made sense of her lifelong feeling that her brain worked differently – an understanding that in turn helped her make her breakout show. Now she is addressing it directly onstage. Because “people don’t understand autism,” she says, “particularly the experience of women on the spectrum. Medicine has not prioritised the study of the female experience at all.” The show is named after the so-called Pouch of Douglas, a part of the female anatomy “discovered” by 18th-century midwife James Douglas. (Douglas is also the name of the comedian’s dog.)

Beyond the gender issue, the show finds Gadsby “trying to pull into focus the ableism that is inherent in the structures we have to navigate. There is an assumption that if you’re not typical then you’re a burden,” she says. “And I think that’s an arrogant assumption.”

That may give the impression that Douglas is as serious-minded as Nanette – which very much isn’t the case, says Gadsby. “It’s really playful, she says. “I’m having more fun onstage. Which is important for me, because I put myself through the wringer performing Nanette.” In Douglas, she riffs on men who play golf, her unlikely new life in LA – and Where’s Wally. (“[He] should have to find himself like the rest of us do.”) Intentionally or otherwise, the lighter tone addresses the most common criticism of Nanette, which is that, because of its seriousness, it wasn’t comedy – and Gadsby, by implication, wasn’t a comedian at all.

Paws for thought... Gadsby with Jasper and Douglas. Photograph: Meredith O'Shea

That arose in part, she says, from the “very different comedy culture [in the States]. In Australia and the UK, where comedians have long been writing concept shows and pushing boundaries, Nanette was not that unusual. But in the land of Netflix specials, it was very different.” But far from losing sleep over the criticism, which she sees as just another attempt to silence a non-mainstream voice, Gadsby addresses it in her new show. “I really enjoy the anatomy of hate,” she says, then corrects herself. “Not enjoy, but I’m fascinated by it. I like to hold what people throw at me and study it and bring it to the stage.” Or, as she has said elsewhere: “Why not troll the trolls?”

At any rate, she is having fun with Douglas, developing a show in front of her vast new audience, who are “very happy in the auditorium before I’ve even done anything”, she marvels. “Which makes the job easier.” She sounds like an artist wholly liberated, her Nanette journey having convinced her that “we really don’t know what audiences want, because we’ve stopped asking them. I thought Nanette was going to be really divisive. But instead audiences went: ‘We really like this!’ And I think that’s fascinating.”

So what is Gadsby going to do with these legions of new fans – and with an entertainment world that is, all of a sudden, at her feet? Well, she is clearly not going to squander the principles that got her here in the first place. “I am now personally a rich and powerful white woman,” she says, hooting with laughter at the thought. “And I have to be careful about that. My platform has always been: I hate people who abuse their power. I want to keep speaking to these identities that I still see as being vulnerable.”

Artistically as well, “it’s important for me,” she says, “not to protect where I’ve got to. Not to write and perform from the standpoint of: ‘I need to hold on to this new patch.’ I want my stance still to be: it’s more important to care about what you’re saying than where it’s going to get you.”

Just as it has been exciting to look on as Gadsby’s life has transformed overnight, it is a thrill to watch her unpick that success and puzzle over how to use it. What seems certain is that she will remain one of comedy’s most considered and critical voices. And that, however she deploys her newfound celebrity, it won’t be accidental. “I have a lot at my fingertips,” she says. “I did take some meetings in Hollywood. And I ended up feeling: I don’t know what I want to do. But I know I don’t want to do something just because I can.

“So I’m going to make sure that what I do is something I can do well. And that will give to the world more than it takes. For now,” she says, “I’m having a think about that. And I’m taking my time.”

Hannah Gadsby plays New Theatre, Oxford, Thursday 24; Royal Festival Hall, SE1, Friday 25 October; touring to 23 November