For a select group of actors, the pandemic was not the worst but the best of times, offering breakout triumphs that were the direct result of the rest of the world being shut in with nothing but the telly for company. Charithra Chandran is among them. After making her debut in Amazon’s teen spy series Alex Rider in 2021, she went on to play one of two Indian sisters who took the Regency “ton” by storm in the second season of the Netflix hit Bridgerton. While she is thankful, she is not naive. When I suggest that hers is a whirlwind success, given that she only landed her first job in 2020, she looks horrified and instantly protests: “I don’t think that at all. I think the complete opposite.”

We’re sitting in a London cafe, close to the flat Chandran, who looks much younger than her 27 years, shares with two university friends. “I’ve potentially had the biggest success, in my professional life, in the second thing I’ve ever done,” she says. “I’m not saying I’ll never do anything grander than Bridgerton. I hope that’s not the case – and I have big ambitions. It’s just rather bizarre that it was the beginning of my career. I think it has really warped my sense of achievement.”

Playing debutante Edwina called for grace and poise of a sort that makes a young woman glitter in a crowded ballroom. This month, Chandran makes her debut in London’s West End with a role that calls for entirely different qualities – not least an ability to hold the stage on her own. In Instructions for a Teenage Armageddon, Chandran plays a traumatised 17-year-old who relives her struggles to cope with an adolescence overshadowed by family tragedy.

Rosie Day’s play – a London fringe hit, which the author originally performed herself at the Southwark Playhouse – is the blackest of black comedies: a character-driven dramatic monologue with flashback video inserts that is so tightly sprung, it would be a spoiler even to give away the protagonist’s name. It opens with the funeral of the girl’s beloved older sister, who has died from complications arising from anorexia. “Mum had been up all night making sandwiches and cake for the after-party,” the girl recalls. “The wake? Weird name for something celebrating someone who is definitely not awake.”

This teenage voice – by turns stroppy, sad, funny, and too clever by half – propels the drama. “I think that’s like what a teenager’s mind is like,” says Chandran. “So many things are happening, mentally and emotionally, and a lot of it doesn’t make sense.” She likens growing up to the development of a caterpillar: “The process by which it becomes a butterfly in the cocoon is really violent. I think the teenage years are like that transformation. There is an internal violence because you just don’t understand. And then, hopefully, something really beautiful comes out.”

Chandran’s own teenage years were spent at a high-achieving private girls’ school in Oxford where, she says, many of the apparently extreme experiences that happen in the play were in fact commonplace. “I would say that eating disorders and sexual assault are pretty ubiquitous – and that’s very, very sad. We know that one in three women will experience sexual assault in their life, so it’s not an ‘extreme’ experience. It’s a very common one. Unfortunately, these are all very relatable.” Did she suffer these problems herself? “I’ve definitely had experience of disordered eating. I wouldn’t say it’s clinical. But I think, unfortunately, it’s probably rarer for a young woman to have a healthy, rather than an unhealthy, relationship with food.”

In her first ballroom scene in Bridgerton, Edwina is asked by her dance partner if she plays a musical instrument. “Many, in fact,” she replies. “But for the most part my education was taken up by more serious pursuits: modern languages, classical literature. I do love to read.” There is an element of this seriousness in Chandran. The only child of an arranged marriage between two doctors from Tamil Nadu in the south of India, she has many accomplishments, from fluency in English and Tamil to playing hockey and netball at county level. She left school for Oxford University where – despite spending most of her time doing drama – she paced herself well enough to earn a first class degree in philosophy, politics and economics.

She laughs off any suggestion that this makes her seem scarily brainy, pointing out that she’s nowhere near as smart as her mum, who is an endocrinologist. Her father is a surgeon and they were classic economic migrants, who arrived in the UK before she was born and separated so early that she cannot remember them being together. Although she is close to both, she was sent to board at a prep school at the age of six because their careers were so full-on. “My parents are polar opposites. I always say I’m in the middle: less hard-working than my dad and less intelligent than my mum. But as a combination, it has enabled me to be high-achieving enough.”

Looking back on her teenage self, she concludes that she was “a bit of a cocky shit”. Then she had a transformative gap year, travelling, waitressing and working in the constituency office of her local MP, which fired up an interest in social justice that she still hopes to pursue. On graduation, she was all set for a job with an international consultancy firm, but had “this niggling feeling” that it wasn’t quite right. So she decided to take another year out, before settling down to “a 70-hour-a -week job”.

Then the pandemic happened. Chandran watched her parents going off to work in their hospitals every day. She set up a food bank “and became introspective about what I wanted to achieve and what I would regret. I was like, ‘I have to give acting a go.’” She sent acting agencies emails that were timed to arrive at 9.05 on a Monday morning – and one took her on. Two months later, she was booked for Alex Rider and, before filming had ended on that, she had landed Bridgerton.

While insisting that she was lucky, she believes there is another side to her good fortune. “In getting signed to my agent, I was a beneficiary of the Black Lives Matter movement. Everybody took stock of how diverse their books were and – whether cynically or beautifully – they were like, ‘Oh, shoot, we need more people of colour.’”

On the other hand, she says: “I also think, ‘How many times have we been passed up for opportunities that we are more than deserving of because we are women, or because I’m brown?’ And that’s what I tell young girls who come up to me and say, ‘Some people at the company think I was hired just because I’m brown, or I wear a hijab, or I’m queer.’ I tell them, ‘How many times did you not get the job because of those very reasons? Own it.’”

She knows her other advantage – being able to play characters 10 years her junior – won’t last. “Considering how Hollywood treats women and ageing, I’m happy to play young for as long as possible. As a brown actor, my experiences aren’t going to be the same as those of my white peers. I don’t have as much choice or opportunity.”

Anyway, if work dries up, Chandran will simply return to her other interests. She has a dream of setting up a micro-community near her grandparents’ home in Tamil Nadu, where she will build solar-powered factories staffed by women who will share the profits – “and show the world that there are other ways of running businesses and communities; that profit maximisation doesn’t have to be the ultimate goal”.

Given her discipline, I wouldn’t put it past her. “I believe life is separated out into periods of purpose and periods of pleasure,” she says, “and my acting career is a period of pleasure.” This doesn’t mean a play like Instructions for a Teenage Armageddon is devoid of purpose. “I hope it will help parents to understand their kids more,” she says, “and teenagers to understand their emotions and experiences. So they feel less of a freak, right?”