Katie Arnstein greets you at her theatre shows by merrily handing out sweets. “I want to say thank you, take the fear away for myself, and immediately start a conversation with the audience,” she explains. After all, there are so many other ways they could be spending the next hour of their lives. “It costs money, time and, during Covid, came with the risk of a journey and an enclosed space. It’s a generous thing for people to be with me. And if they don’t like it, they’ve had a rhubarb and custard.” The shows are carefully confected by Arnstein, who has emerged as one of our most captivating storytellers, with her soft-centred yet never sentimental explorations of hard subjects. Her first three productions formed the It’s a Girl! trilogy about sexism and sexuality. Her latest piece, The Long Run, is a bracing account of her mother Jane’s treatment for bowel cancer. Putting audiences at ease is essential: “I’ve never changed my mind because someone’s yelled at me. But I have if someone’s spoken gently to me.” The starting point for The Long Run was the time she spent taking her mum for radiology: “I was freaking out for two months.” In the waiting room she observed a man escorting his neighbour, who was being treated for a brain tumour and had no one else to drive him. Arnstein began to build a show about strangers helping each other out, interweaving a fictional plot involving an older gent in the hospital who is training for a marathon. This provided a chance to write about the London Marathon, Arnstein’s favourite day out. She has watched it almost every year since relocating to the capital from the West Midlands. “I can’t run for a bus so it’s genuinely remarkable to me. People are cheering on strangers!” The Long Run, directed by Bec Martin, incoming artistic director of innovative London theatre New Diorama, has a traverse stage with the audience on either side, as if spectators at a marathon. It feels as though we are carrying along both Katie and Jane (who never appears yet is vividly evoked). Jane, a retired headteacher, has been an enthusiastic promoter of Katie’s career, including approaching a major agent on her behalf. “I woke up one morning CCed into an email she had written,” recalls Arnstein with wonder and horror. In the letter, Jane championed her daughter’s sterling performance as a magical blue cat in a Christmas show. Arnstein was straight on the phone: “Mother, in the same way that I didn’t try to get you a headship, please stop trying to get me a job!” She laughs. “Mum’s a big fan of the strong email.” There’s a pause and she gives a mock nervous look. “Have you heard from her yet?” With The Long Run, Arnstein aims to reframe the way we speak about cancer. “I hated that it was a ‘battle’ that she could ‘win or lose’. I hated the ‘fight’ terminology and the talk of ‘beating it’ … because I don’t think you can lose to it. I think you can get the time and the treatment you need and deserve, or you don’t. My mum did – and I am so grateful – but if someone doesn’t, it isn’t on them. They didn’t ‘lose’.” Cancer Research is lending support to the show, which will tour next year and hopefully visit the Edinburgh festival. Arnstein won acclaim at the fringe in 2019 for Sexy Lamp, the middle part of her trilogy, named after writer Kelly Sue DeConnick’s test about the value of a drama’s female character. (If you can replace them with a lamp and the plot still works, it fails the test.) With sparkling wordplay and ukulele songs, Sexy Lamp playfully revisited Arnstein’s early experiences as an actor but added some devastating examples of the industry’s cruelty, including an audition during which she is continually asked to remove more clothing. Her shows originate from personal experience, she says, adding that sometimes real life wouldn’t be believable. Take the time when she experienced everyday sexism while actually reading Laura Bates’s Everyday Sexism. “This group of men came on the train, sat around me and were passing a bottle about. They were like, ‘Oh, are you a feminist?’ They took the book off me and I felt like I was six years old. The carriage was full and nobody stepped in. I had my hair in a bun and when they got off one of them grabbed it and pulled my hair out. I was really shaken. Then, when I was waiting for the bus home, there was a guy on crutches yelling at a woman. I said, ‘Please don’t yell’ – and he hit me on the back of my legs with his crutches. I wanted to talk about that journey but nobody would believe it so I had to rein it in.” That story was included in her first show, Bicycles and Fish. There were seven audience members at its first performance in 2018 at London’s Vault festival – “and I was blood-related to four of them”. The following year Sexy Lamp won an award at Vault, which provided financial assistance for an Edinburgh run. “Lightning in a bottle,” she marvels. She even made a profit in Edinburgh. The final part of the trilogy, Sticky Door, about a year of sexual encounters, was at the fringe in 2022. That time, “I only lost £400,” she says, with a knowing laugh about the perilous fringe economy. “People go, ‘Well done!’ but imagine if you got mugged and £400 was taken!” Vault festival, a vital launchpad for theatrical talent that gives artists a favourable box-office split, has been under threat. Even over the course of a brief career, Arnstein – who is 32 – has seen conditions toughen in the industry: “All theatres talk of a last-minute booking culture [with audiences]. There aren’t many pre-sales so there’s a higher financial risk.” She funds her work through a mix of jobs. “This year I’ve been a waiter, a miller, a childminder, done customer service” – and it’s been like this since she left Birmingham School of Acting (now Royal Birmingham Conservatoire) in 2012. What was her first performing job? “A pantomime that toured northern garden centres.” To add to the glamour: “I was also the driver. The most humbling bit was when this kid came up to me at the end, tugged on my dress and said, ‘I didn’t like it.’” Disappointed with the scripts she had as an actor, she gave writing a go – and is now doing so for other performers. Her first monologue for TV, the darkly comic Wolverine Woman, was produced for BBC Three’s series The Break. It stars Olivia Swann who, with a door key held claw-like between her fingers (“Shout out to Hugh Jackman!”), is trying to get home alone after a work do. This, as Swann says drolly to camera, comes with “edge of your seat, heart in your mouth thrills”, as well as safety strategies learned at Brownies. Arnstein is delighted with Swann’s performance. “I knew I wanted the main character to be funny, to seem like a strong woman and still be vulnerable in that situation. I wanted people to think about their best mate being followed home, or their sister.” The eldest of three sisters, Arnstein drew on memories of the safety talk given to girls at her school while the boys were taken to watch a movie in another room. Too often, she says, the problem is presented for women to solve. “There’s no separate session for boys about how not to follow people home.” As a solo fringe theatre performer, her own working conditions can be precarious and unpredictable, in an industry that has been slow to protect freelancers. Arnstein studied drama in the days before intimacy coaching and is scathing about the student roles she had – mostly written by male playwrights. “In my third year I played a grandma and a 90-year-old maid.” She laughs, adding: “I don’t mean to brag!” She grimaces at the memory of following advice to do an acting showcase performance in a bra. Novice actors have too often been asked to test their limits, she says, rather than find their voice. Writing her own roles is empowering but complicated, she adds. “I do shows about taking up space but feel all the time like I don’t deserve to be there.” One solution is to read the glowing reviews she has written for her own performances. No, the ego hasn’t landed – this is the sage advice of her friend, playwright Jon Brittain. “He said if you’re having a day when you’re stuck, write a review of your show. I did it for Sexy Lamp, ‘Katie Arnstein has written a show about this and it makes you feel like this …’ Then you get a blank page and think, ‘OK, how do I make that happen?’ Then just work backwards.” The Long Run is at New Diorama, London, 28 March-13 April 2024, and on tour. Wolverine Woman is on BBC iPlayer