It’s clear from the off that drama, with a beguiling lick of irony, never trails far behind Tracy-Ann Oberman. Before she’s fully arrived at a sparkling, minimalist dressing room in the upper reaches of the Hampstead Theatre, in North London, she’s already knee deep into her explanation as to why she’s late: “Cooking; hot oil; a phone call; good God! An actual fire!”

Less clear, at least to begin with, is why an interview about her adaptation of Chekhov’s Three Sisters would require the presence of a press officer.

But Oberman is used to supervised dealings with the press, thanks to her 18-month stint as Chrissie Watts, Dirty Den’s second wife, on EastEnders. There, storylines were so fiercely guarded that even the cast weren’t sure how they would play out.

When, one rainy night in February 2005, she killed Den with a doorstop shaped like a small dog, the show’s producers shot multiple endings to ensure the cast couldn’t leak the plot.

Three Sisters, on the other hand, is famous for not having a plot. When it opened in 1901, Chekhov’s study of the quietly despairing Pozorov family caused critical confusion, precisely because so very little appeared to happen. The sisters yearn for Moscow, for a transformative love, for some kind of grand rupture or resolution, and, over the space of three, fictive years, Chekhov doggedly refuses to comply.

The only radical surprise of Oberman’s version, co-written with Diane Samuels, is that the Pozorov sisters are now Jewish, English, and living in postwar Liverpool .

“It does alter the play, butnot as much as you’d imagine,” Oberman says. “There’s this tight-knit community, philosophising like mad, completely ignoring the social change on their doorstep, pining for their halcyon days elsewhere. Everybody’s flirting or outright shagging each other, or eating, and there’s so much pain and longing and humour; huge waves of conflicting emotions. I thought, wow, this is a completely Jewish experience.” That thought first occurred in 1991, when, aged 23, Oberman studied at the Moscow Arts Theatre School, as part of her Guildhall School of Drama training. “Itfelt so close to my own life, it was a revelation.”

That said, Oberman is not an orphan, has only one sister, and is “ecstatically” married to the music producer Rob Cowan, with whom she has a daughter, Anoushka, aged 18 months. She hails from a North London legal family who “weren’t wildly happy” about her career choice. “My parents were always making me watch Rumpole of the Bailey, going ‘You see? It’s just like acting, you make things up, you wear a wig and a funny outfit. Why not the law?’ But I just always, always wanted to act, as far back as I remember.”

Four years at the RSC on graduation were followed by astab at stand-up, which she deemed “too terrifying”. As a sketchwriter and comic performer, though, and in theatre rep, Oberman had “what you’d call a solid, jobbing career”, most notably in Big Train and Lenny Henry in Pieces.

Then came EastEnders. Despite the producers deciding the week after her debut early in 2004 to write out Leslie Grantham for vilifying fellow cast members before a web-cam, her character wasn’t axed. “It was a strange time,” Oberman says, “but Chrissie was fabulous. I’d look at the storylines and think, ‘Digging up yourhusband. Talking to his dead body. Right. How would Bette Davis play this?’ It was so over the top, so Grand Guignol, I had a blast. And I got out in time, so I didn’t get stuck.”

Leaving Albert Square in November 2005, Oberman was deluged with offers. A lifelong Whovian, she appeared in Doctor Who, playing an upper-crust alien collector in the second series finale. And, on discovering she was pregnant, had to turn down another, from Mike Leigh, who was preparing his play Two Thousand Years at the National.

Leigh’s “Jewish play” gave Oberman the impetus to knuckle down on her own. She and the writer Diane Samuels had begun collaborating on the script, Samuels suggesting setting the action in postwar Liverpool, where American GIs congregated in droves, the dream of Israel burnt bright, and where, in August 1947, antiJewish riots ripped through the city. Those riots replace the third act fire of Chekhov’s original. But, Oberman insists: “This is not a political play about the state of modern Israel. It describes a historical moment, when Zionism was a shiny, hopeful ideal. Take from that what you will.”

They workshopped the play with Leigh’s original, all-Jewish Two Thousand Years company. “It was important that this was authentically Jewish,” Oberman says. “We didn’t want klezmer, ‘oi vay’ stereotypes. And I had a feeling that an all-Jewish company would generate a great sense of warmth and community.”

And did they? This is the question that perks up the press officer. Oberman shoots a glance over her shoulder, covers the mike and mouths “No”. To the next question, and why aren’t you in it? she repeats the gestures, adding, sotto voce, “Thereby hangs a tale.”

For the moment, it’s not one Oberman is telling. It’s also one she seems to be assuming I know already. I don’t. But a bit of research later suggests that Oberman wanted the role of the middle sister, May Lasky, and was offered instead the social climbing sister-in-law Debbie. She admits to turning it down, officially because she was “too close to the material”. Said rumours also suggest that the director, Lindsay Posner, was uncomfortable with how far the script had veered from Chekhov’s original. And worst of all that old friends Oberman and Diane Samuels had such a rumpus over the writing of it that they can no longer sit in the same room together.

I can confirm that they won’t do interviews together. On the phone Diane Samuels duly denies the rumour of an outright schism: “Without some argy bargy, no creative process could happen. But the cast are doing fantastic work and we’re all thrilled with the project.” When asked if she’s properly fallen out with herco-writer, Samuels says she’s late for rehearsals. When told there are rumours that she has, she advises me not to confuse rumour with fact. When asked if she and Oberman are in fact still friends, she replies: “Well, we’re still neighbours.”

True to garrulous form, Oberman is more candid. “This process has been really hard,” she says. “I’m a natural collaborator, but I’ve never written anything so close to my heart. It’s been really, really difficult for me to let it go. This production might not be my ultimate vision of the play, and in the future I fully intend to play May. I have to. I actually think she is me. But I’m determined now to trust, sit back and enjoy it with everybody else.”

Perhaps it was inevitable that tensions would mount beyond the bounds of creative frisson. As Oberman observed of Chekhov: “He understood that comedy and tragedy turn on the flip of a sixpence. It’s true of me, and it’s very present in Judaism. The sweet and the salt of life are always together. We’ll be laughing and crying, hugging and tearing each other apart in the same breath.” Sounds exhausting. “Yes.” She laughs loudly, “on that I think we’d all agree.”

Three Sisters on Hope Street, Everyman, Liverpool (www.everymanplayhouse.com 0151-709 4776) until Feb 16; Hampstead Theatre, London NW3 (www.hampsteadtheatre.com 020-7722 9301), Feb 21

Editor's choice

• The 100 Best Films of the Decade
• 70 facts you didn't know about Marvel
• The 50 Biggest Movies Of 2010