FOR many a writer, the indispensable tools of the trade are a laptop and a cafe with free wi-fi.

With Alecky Blythe, it's a Dictaphone every time.

It was her trusty recorder that Blythe took to Ipswich in 2006. The Suffolk town was frightened and felt under siege. Five women, working as prostitutes, had been found dead in quick succession and talk was of an "Ipswich Ripper". Blythe spoke to residents in the area immediately affected, and these interviews became the basis of an award-winning musical drama, London Road, that has now been made into a film, out next week.

Blythe specialises in verbatim theatre, which turns interviews about real events into dialogue spoken by actors. She learned about it when she was starting out as an actor and wrote her first play, Come Out Eli, using the method.

"I wasn't getting any work so I decided to make my own work. I really only had plans to make that one play to try to get an acting agent, but the play ended up being more successful than I had imagined and I got a literary agent off the back of it. So my career really went in a different direction to what I planned."

Blythe works at what she calls the "extreme" end of verbatim theatre in that the actors don't just say the words, but use the precise manner in which they were spoken. Pioneered by the actress and academic Anna Deavere Smith, verbatim theatre has been used to explore everything from the LA riots (Deavere Smith's Twilight: Los Angeles 1992), to rail privatisation (David Hare's The Permanent Way). As far as Blythe knows, London Road is the first verbatim musical.

It came about when Blythe met the composer Adam Cork at a workshop at the National Theatre in London in 2007. Blythe had some of the material that would eventually be used, but much more work would be needed, requiring return visits to London Road, before the duo had a piece. Both learned a lot from each other.

"I'm not a big fan of a lot of conventional musicals," says Blythe, 42. "I cringe a little bit when they go from the speaking to the singing and there is that sort of lift-off moment which can often be quite cheesy. So I wanted to see if I could do a verbatim take on it which was less cringy."

Cork was intrigued then delighted with the method. "When it's done well, it's almost like the actors are being possessed by the spirits of the people she's interviewed."

When Blythe first went to Ipswich the media were everywhere. It was important to the Londoner that people knew right from the off that she was not a journalist but someone creating a play.

"At that point I didn't know quite what the play was. Of course I got some nos, but I think the people who did respond to me were the ones who felt that maybe their story wasn't being told. I wasn't asking them the big questions like who the murderer was, did they know the girls. I was more, 'What is it like for you living through this?' People did want to talk about that."

The killer, Steve Wright, lived on London Road. In 2008 he was sentenced to life for the murder of five women. When an area is linked to a dreadful crime, it usually only falls to residents to say they couldn't believe such a thing would happen where they live, or that the perpetrator was a quiet sort who kept themselves to themselves.

London Road goes deeper in showing how residents felt not only about the atmosphere of fear and suspicion, but the fact that their street had been blighted by kerb crawling before the murders. One says of the prostitutes and their clients, "They were a complete pain in the neck."

Other contributions, one in particular, are more brutally honest. As this is verbatim theatre, it went in as said. In that instance, Blythe she told the interviewee what would appear in the piece. "I needed to check she was okay with that and she was." It was kept in not to shock, says Blythe, but because it was an honest comment.

The film has attracted a best-of-British cast that includes Olivia Colman, Tom Hardy and Anita Dobson. This was a new way of working for all of them and one that took Colman, in particular, time to get used to.

"I can learn a page of script fairly quickly, just from years of practice," says the star of Broadchurch and The Iron Lady. "But it took at least ten times longer to learn a page of Alecky's verbatim script. I did start to wonder, 'Why the hell did I say yes...?' But having been fearful of it and close to tears at times, I'd say it was one of the most enjoyable and fulfilling jobs I've ever had."

Other admirers of the piece hailed from further afield. When the play ran at the National Theatre in London, a collection would be made after the performance for a charity in Ipswich working to get vulnerable women off drugs and off the streets. Nick Holder, one of the original cast, recalls a conversation he had one night.

"An American gentleman came up to me. He was in tears. He said, 'How did you do that? How did you do that?' He put a ten-pound note in the bucket and walked outside. Then he came back in and put another ten-pound note in the bucket, and said, 'I've never seen acting like that. That's what I've always wanted to do.' He walked out, then came back in again and said, 'Please pass on my regards to everybody. That was the greatest ensemble acting I've ever seen'. That was Dustin Hoffman."

Blythe met Hoffman too, and, like many another audience member, he wanted to know where the idea had come from. "On paper it does sound like a very weird concept," concedes Blythe.

She has kept in touch with London Road residents. After we spoke in London she was heading to Ipswich to show residents a preview of the finished film. Some of them appear in the film in a street scene. It is a changed place, says Blythe, and they are a community transformed, one in which people know and look out for each other. Another positive, says Blythe, is that Ipswich has become something of a beacon for projects aiming to get women out of prostitution. Sadly, as one prostitute says in the film: "It took all that for anyone to start helping us."

Now that London Road has made it to the big screen, Blythe can return to other work, including a short film for BBC Four's Dialogues strand. Having started writing her own plays because she could not get an acting agent, she now finds herself with one.

"So there you go," she laughs. "If you stick at it long enough, it can happen."

[itals] London Road live premiere, 6.45pm, June 9, at Cineworld Renfrew Street, Glasgow; Fountain Park, Edinburgh; Union Square, Aberdeen; Cameo, Edinburgh; DCA, Dundee. General release, June 12