Deidre Dare draws heavily on a cigarette. “It’s outrageous,” the 44-year-old American says, pursing her lips and flashing her eyes. “What I wrote is fiction. It’s neither about the firm nor the people I work for. Why can’t I post fictional writings just because I work for a law firm? They don’t have a leg to stand on. If I get sacked I’ll sue. It’s about freedom of speech.” She pauses. “They’ve picked a fight with the wrong girl.”

In a fur coat, black leather trousers and a glittering belt that shifts to reveal a pierced belly button, Dare is, this week at least, Russia’s most talked about import. A corporate lawyer with Allen & Overy, working in their Moscow office, she began posting chapters of her steamy novel Expat on the internet four months ago, thinking it was “nothing more than a bit of innocent fun”.

Everyone at work knew about her online account of the life and bedroom antics of Dasha, a young foreign woman in the Russian capital, and the London-based firm suspended her when she refused to take it down. The company blocked her BlackBerry, e-mail and electronic work pass and claimed that she had brought it into disrepute. She now fears she may be sacked from her £150,000-a-year job for her resistance.

A quick look at deidredare.com reveals photographs of the lawyer reclining on a sofa in lingerie, as well as 11 chapters of the novel: “There is something thrilling about being in bed with a Frenchman, even if he does have a small c*** which he can’t get up, I thought, as Pierre gently kissed my eyelids and stroked my face. I sighed as if in pleasure, when, really, my mind was occupied with the thought that it is disappointing how European men seemed to have little boy c***s.”

Nor is Dasha very impressed with Germans: “They have a tendency to make uninteresting small talk while f****** you (‘Do you think it will be cold tomorrow? If so, should I wear two pairs of socks?’) . . . Germans are really some of the most boring people on Earth.”

Now, far from going quietly, Dare is gearing up to take on her employer in what could become a landmark case. “It’s getting crazy,” she says, when we meet for coffee in Moscow. Briefly accompanied by her Russian boyfriend, a lawyer 12 years her junior, she seems tired but is in no mood to compromise. After all, she could repeat the success of Petite Anglaise, a young British woman living in Paris who was sacked by her employer when it discovered her identity as the author of an indiscreet blog. She subsequently won a court case against her bosses and became a publishing success.

And, for the moment at least, matters seem to be going Dare’s way. Before the story broke, her website was visited by a mere 3,500 people a month. Now 800,000 have accessed it in a few days, Dare claims, and a Moscow newspaper has even asked her to write a weekly column called Sexpat. She has also been approached by more than one publisher and hopes to publish her book The Marriage Delusion – in which she argues that matrimony should be abolished – in a two-book package along with Expat.

“I’m being inundated with e-mails from across the globe, people expressing support as well as quite a few men making advances,” she says. “I’ve received messages from people in Iran and Jordan. And a lot of Italians, wanting to prove that they are good in bed.”

Born in Brooklyn to a Russian-Jewish father and an Irish mother, Dare, whose real surname is Clark, always dreamt of becoming a writer. She penned her first novel at five but went on to study law. She was later offered a place at New York’s best journalism school but chose to stick to law because of its high salaries.

She has worked as a corporate lawyer for nearly 20 years, first in the US and then on postings in London, Sydney, Singapore and now Moscow. Her interest in writing did not wane, however. Over the years she wrote two books – both unpublished. She called the first, about life in a law firm, Big Swinging Dicks. The second, Slut, is a work of fiction whose main character is prone to multiple affairs.

She moved to Moscow last year, only a few months after joining Allen & Overy, at a time when the Russian capital was booming. She lives in a luxury six-bedroom flat across from the US embassy, which in Expat is often the setting of Dasha’s raunchy sexual exploits.

She is, however, keen to empha-sise that the novel is, mostly, invention. “I have never had a bad time in bed with a Frenchman,” she says. “It’s not meant seriously. In fact I always thought the sex scenes were pretty tame. I can’t see anyone getting turned on.”

Inevitably there are elements that are familiar. Dasha is a New Yorker, albeit 10 years younger than Dare, and some of the novel’s events, such as a big row between BP and three Russian oligarchs over their joint oil venture, are real.

“As with all fiction some elements are autobiographical,” allows Dare, who in person is engaging but possibly a touch reckless, and certainly not the fiercely seductive vamp the book might indicate. The novel, she says, is simply intended to give a first-person insight into the lives of Moscow’s large expatriate community. “Mostly, however, it’s made up. It’s impressionistic. Of course there’s heavy drinking and casual sex among expats.

“I love Moscow. We suit each other. It’s chaotic and free. Something happens every day.”

Or as Dasha sees it: “Anything goes in Moscow: you can drink as much as you like while driving, you can wear your seatbelt or not, you can smoke wherever you want, including elevators and restrooms, you can buy any drug over the counter, you can eat as much fat as you like, you can f*** anyone you want (including the guy who is interviewing you for a new job, I found out once) and, maybe most importantly, you can dress like a complete slut if you feel like it.”

Dare doesn’t seem entirely sure where Dasha ends and Deidre starts. As she lights another cigarette, she says she was going to wear jeans to our meeting but thought that I should “be given a small taste of Dasha, which means black leather pants in the morning. I’m not a straight person and, yes, I’ve slept around – it’s hardly difficult to bed a man – but I’m not Dasha. I’m faithful when I’m in love. I’d better be now that I’m with a Russian. It’s not a good idea to betray a Russian.”

As I walk Dare across the road back to her flat along a treacherous pavement covered in ice, she holds on to me and talks of her admiration for Larry Flynt, the pornographer who took on the US government to defend the country’s first amendment (freedom of speech). She recalls her father, a die-hard communist until his death, who had been so disappointed when she became a corporate lawyer: “He thought I’d sold out.”

Dare gives me a brief tour of her flat, which includes a small gym. Does she use it? “Of course! How do you think I keep such a great figure?” she says.

But unlike Dasha the man-eater – who at this point presumably would have had me for breakfast and then lamented my performance on the web – the lawyer is on best behaviour. I escape relieved that I have not let down the male population of Europe. This, however, is unlikely to be the last time I hear of Dare. After all, she seems to be revelling in it.

“I feel like my life has changed overnight; a bit like Byron,” she says. “Never in my wildest imagination did I think that my novel would attract such attention and so much fuss. But I have no regrets and I won’t back down. Even if I suddenly made a lot of money with my writing, I’d still sue if I got sacked. It’s about freedom of expression. It’s very important. My dad would probably be proud of me. He’d say I infiltrated the system, and maybe he’s right.”

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