Abi Morgan: Meet Britain's busiest writer

It's a sunny Thursday in Crouch End, north London and Abi Morgan has escaped the racket of the building work going on at home for the peace and quiet of a local café. She's here to talk to me, but also, crucially, to put the finishing touches to the first two episodes of series two of The Hour, the BBC's stylish 1950s newsroom drama, whose first series attracted an average of 2.1 million viewers.

In just a couple of hours, the Bafta-winning writer says, she will deliver those episodes, starting the ball rolling on a storyline set 10 months after we left Bel, Freddie and Hector, their controversial current-affairs programme gone down in flames. "I still always think the greatest moment for me as a writer is when I press that button and send the first draft of the script," she says. "It never gets better than that moment and I always have that feeling: the house feels lighter, I feel lighter, you have a glass of wine and it's, 'phew, I got it in.'"

Filming on series two of The Hour won't start until next year but Morgan doesn't have to go far from home to remind herself of the torrid atmosphere of the drama she created: the café we are sitting in is not 100 yards from Hornsey Town Hall, the 1930s building that fans of the first series will recognise as the BBC's Shepherd's Bush Lime Grove Studios. Morgan was on location a lot during filming, she says, as well as being "very involved" in numerous other aspects of the programme's creation, including making casting and editing decisions. "I think in some ways there's a point as a television writer that 'executive producer' is the natural credit you get and it can be a vanity title or you can make of it what you want. It was a very hands-on experience for me... It's a great thing for a writer to have that experience."

Casting, in fact, is an area that specially interests the writer. "I think casting is everything," she says. "You get a great cast and – certainly as happens in The Hour – so many of those performances on the page were transformed by those actors who took those parts and made it into something completely different. It has been a very exciting alchemy on that show."

Morgan has always written for particular actors – "even if they don't end up playing the part"– and the process was no different on The Hour: "I wrote Freddie with Ben [Whishaw] very much in mind. [The character] was a genius slightly spinning out of control and he was very much in mind." Romola Garai, who plays Bel, is, according to Morgan, "a very, very intelligent actress. She's terrific. She brings instant glamour and appeal."

However enjoyable the hands-on process was for Morgan, she was also aware of the danger of getting overly caught up in other roles at the expense of the writing. "You have also to be able to shut off and go, 'now is the day I write'," she says. She writes at home mostly, in the house she shares with her partner, the actor Jacob Krichefski, and their two young children; the work is vital for her well-being. "If the world is in complete flux for me and life is falling apart, if I just manage to get myself in front of a computer or at my desk, it calms. It's really simple. Genuinely, if I don't write every day, the funny tics and the madness appears."

Aside from The Hour, Morgan has just finished Lovesong, a new play for the physical theatre company Frantic Assembly, which begins a UK tour at the end of the month. It is her first full-length play to be produced in 10 years, during which time she has won plaudits and awards for her film and television work, including the 2005 Best Drama Serial Bafta for Sex Traffic.

Lovesong sees her reunited with the company's artistic directors, Scott Graham and Steven Hoggett, with whom she last worked on her 2001 play Tiny Dynamite, one of a series of productions that brought Morgan to prominence as an important voice in UK drama. Tender, the play that followed, earned Morgan an Olivier award nomination for Most Promising Playwright.

After her long sojourn in the worlds of television and film, Morgan admits to being "a little bit nervous" about the return to writing for theatre: "I have written a couple of plays during that time but I have genuinely found plays really hard to write... It's partly focus and partly I really feel like the domain of the playwright is the voice that has something to say. I think that perhaps there was an urgency to the way I wrote in my twenties. I don't know if you just get fatter and more complacent the older you get, but I definitely find that not just my motivation, but what I want to write about, feels very different and the energy in which I write feels very different."

By a quirk of timing, less than a month after Lovesong opens at the Drum Theatre, Plymouth, another new play of Morgan's, 27, opens at Edinburgh's Royal Lyceum Theatre. Based on a book by the Alzheimer's expert David Snowdon, and set in a convent, the play addresses issues of ageing, faith and the loss of the self. Its director is Vicky Featherstone, the artistic director at the National Theatre of Scotland and another member of the team who worked on Tiny Dynamite. It is, says Morgan, "an extraordinary time". Lovesong is the story of a love affair told over many years, with young and old versions of the same couple going about day-to-day life in the home they have made, not quite interacting with each other, but inhabiting the same space. It's a subtly emotive piece of work that I suspect will have audiences weeping into their programmes.

Reading some plays, you get the sense that they could work equally well on television or film, but Lovesong is patently a piece for the stage and nowhere else. "I feel like writing for theatre uses a very different part of my imagination, and Lovesong, more than anything else I've written, is a sort of tone poem in a way," agrees Morgan. "It certainly doesn't have a four-act structure – it's a series of scenes – but there is for me a simple kind of poetic concept, which is the ageing of two different couples in two different periods in their life, that you realise are one."

The play is dedicated to Morgan's father, the director Gareth Morgan, who died three years ago. She describes her relationship with him as "quite complex" and has talked about her parents' difficult break-up in previous interviews, recalling tough times after she and her mother, the actor Pat England, were left high and dry. The period leading up to her father's death was influential on Lovesong, though she only became aware of that after she'd finished writing it. "It was the first time I'd watched the decline of someone. The play is about mortality and the decline of the self... so in a way it felt right to dedicate it to him because it felt like it had come out of that period in my life." The dedication itself, she says, was "a very last-minute thing".

Morgan didn't have anything professionally produced until the age of 30, when her play Skinned was staged at the Nuffield Theatre in Southampton in 1998. She pooh-poohs the romantic notion "that if you're a writer, you were writing from the day you were born. I wrote one really cruddy poem when I was 15." But Morgan acknowledges that her theatrical upbringing – a childhood spent in green rooms and costume departments – made her aware of the possibilities of a career in the arts. "It was a very rich world... I realised there was a profession in which you could tell stories in a very creative, artistic way. It was never an option that you couldn't do that."

When it comes to the business of telling those stories, Morgan is not content to rest on her laurels. She recently collaborated with the Turner Prize-winning artist and film-maker Steve McQueen on Shame, which won its leading man, Michael Fassbender, the best actor prize at the Venice Film Festival earlier this month, and is due for release in January. McQueen was something of an inspiration for Morgan: "Steve has taken me to somewhere else in my writing that I don't think I'd have gone without him... I don't think writers or directors like Steve McQueen come around that often."

Another Morgan-penned feature to be released in the new year is The Iron Lady, the hotly anticipated Thatcher biopic starring Meryl Streep. She found the actress to be hugely impressive: "I worked a little with her and she's just amazing: so finely tuned in decision-making. The great gift of an actress like her is that she's very down to earth, and true to what she does."

In addition to these films, the two plays about to open and series two of The Hour, Morgan's two-part adaptation of the Sebastian Faulks novel Birdsong is in post-production and she is developing a script for Film4 based on the suffragette movement. Of the most hectic period of her professional life so far, Morgan says cheerfully, "It's just been an intense last year... all the buses coming at once, really."

Tomorrow she'll be in rehearsal for Lovesong and next week she goes up to Scotland to look in on rehearsals of 27 for the first time. For now, though, those episodes of The Hour need delivering and it's time for me to leave the most prolific woman in UK drama to her "send moment".

'Lovesong' opens at the Drum Theatre, Plymouth (01752 230440) on 30 September, before touring to the Warwick Arts Centre, Coventry (024 7652 4524), West Yorkshire Playhouse, Leeds (0113 213 7700), Chichester Festival Theatre (01243 781312), Lyric Hammersmith, London (0871 221 1729) and Citizen's Theatre, Glasgow (0871 221 1729). franticassembly.co.uk