Most pretty young actresses would sound preposterous if they came out with: “The process of learning about the whole capitalist system that underpins our economy was really enjoyable.” But then most pretty young actresses, unlike Amara Karan, haven’t got a 2:1 in politics, philosophy and economics from Oxford University and spent two years working in mergers and acquisitions in the City.

Now, to cap her somewhat daunting CV, she’s turned to acting. Barely more than a fortnight after leaving drama school, she was auditioning, successfully, for Hollywood big shot Wes Anderson’s new film, The Darjeeling Limited. She clearly isn’t kidding when she says she’s always been competitive and ambitious.

Yet far from being a monster, Karan, 25, turns out to be a nice girl from Wimbledon, still wide-eyed with excitement at her good fortune. She’s happy to be photographed wearing the contents of her own wardrobe – Topshop, mainly, and a beloved Wimbledon High School sweatshirt – which she has tipped into a couple of carrier bags and lugged across town.

In The Darjeeling Limited, her well-received big-screen debut – indeed, as she points out, her first professional acting job full stop – she plays a train stewardess who has an affair with one of three brothers travelling across India. Starring Owen Wilson, Adrien Brody and Jason Schwartzman, it’s the sort of funny, quirky film you’d expect from Wes Anderson, the man who brought us The Royal Tenenbaums and The Life Aquatic with Steve Zissou.

But Karan, who says she was “auditioned to death” for the role, pauses for a long time when asked whether the two months she spent on the shoot in Rajasthan were fun. Finally, she says that she learnt a lot from the filming process, and enjoyed playing her character, Rita, and having the chance to go to northern India (she’d been to southern India before, but never the north).

“It was a work-driven set,” she concludes. “Every single person in every department was working to 100 per cent. Except Wes, who was on 200 per cent.” As for Owen Wilson, the troubled actor who recently ended up in hospital after an alleged suicide attempt, there was no hint nine months ago when Karan last saw him of what was to come.

“Owen was really fun and generous and into the work,” she says, “and very curious, always asking questions about people. We’d chat away about acting and stuff. It’s very sad what happened, but I’ve not been in touch with him over the past nine months.”

Karan knew from the age of ten, when she appeared in a school play, that she wanted to be an actress, and acted throughout her degree in the Oxford University Dramatic Society. Her Sri Lankan parents moved to England from Zambia two years before she was born because her father, a financier from whom she is estranged, thought there were more work opportunities. (She politely declines to elaborate on why she’s estranged from him.) She went to the academic Wimbledon High School, where she excelled, and says she always wanted to come top in everything. But in spite of knowing that acting was what she loved, she shied away from it as a career.

“The honest view is that it’s impossible to make a living out of acting and I was very sensible about that. I thought, given that I’m so academic, I should harness that. I never admitted to myself how much I loved acting, because I thought it’s just not prestigious enough.” She imagined she’d be a barrister or doctor, and read PPE because she thought it might be useful if she went into law.

“I was never that bothered about what my parents wanted me to do,” she insists, “and they didn’t really force anything on me. I think I just had that desire to be successful.”

The other problem was that she simply didn’t know how to get started in a career that doesn’t have an application form. “It seemed to me that a lot of the people who had a chance of being an actor had started years ahead of me, or had connections in the business. It seemed to be impossible, to do with luck or extreme beauty.”

But although she enjoyed the intellectual challenge of banking, she became convinced that she had to give acting a go. Ever the pragmatist, she applied to drama schools first, to see if she was offered a place, before giving up the day job, and she spoke to friends who worked as casting directors or at actors’ agencies about whether there was a gap in the market for a good, young British-Asian actress that she could fill. Reassured that there was, she took the plunge.

“I viewed myself as a commodity. I had to find a way to position myself. I see myself, and my work, as a business and look at things from an investment and strategic point of view. I think I’ve been so successful because of my hard work and because of the business-minded approach I learnt working in the City.”

Her mother, however, was less convinced: she burst in to tears when Karan told her she was resigning, and still hasn’t come to terms with it.

“She was devastated,” remembers Karan. “She watches Tamil, not Western, films, so it doesn’t mean anything to her. She’s just like, ‘Well, you’re an actress, that’s really embarrassing.’”

But as Karan is finding out, the reality of making films is hours of waiting around with nothing to do. “Oh God,” she groans. “It was soooooo boring… Unbelievably boring. I find waiting hard, which is something I’m working on. Apparently, Dame Judi Dench knits. Maybe I should take that up.”

On the upside, Bulgari recently asked her agent if it could drape her in jewels for a premiere and, being new to the business, she’s refreshingly unjaded about doing publicity junkets. In fact, she’s actively enjoying her first in New York, at the Ritz-Carlton. Although Owen Wilson was notably absent, co-star Adrien Brody had been calming her nerves with advice and encouragement.

As for the future, she’d love to do serious theatre some day, but once she’s finished promoting The Darjeeling Limited there’ll be the new St Trinian’s movie – in which she plays a posh looker, Peaches – to publicise. She went straight from filming in Rajasthan to playing a schoolgirl at a disused boys’ boarding school in Henley, alongside model Lily Cole and Colin Firth – who was, “really fun, really great. He’s just always going to be my Mr Darcy.” And as for her, “I’m single and looking!” she laughs. “D’you know anyone?” n

The Darjeeling Limited is the closing gala film at The Times BFI 51st London Film Festival on November 1, and goes on general release on November 23. For further festival information, contact the BFI (020-7928 3232; www.bfi.org.uk ) or visittimesonline.co.uk/lff

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