Liz Lochhead: The light relief of tragedy

It's raining, and the woman heralded as "Scotland's greatest living dramatist" is trying to foist an umbrella on me. "It's only an old one, go on, take it," she says, concerned I'll get soaked as I leave her flat. The gesture sums up poet-playwright Liz Lochhead. She's a people person.

Despite covering such vastly different ground as Mary Queen of Scots Got Her Head Chopped Off, Perfect Days and the Euripides adaptation Medea, Lochhead's plays are all concerned with what it is to be human. Her latest adaptation, Thebans, which is playing at the Edinburgh Festival before heading south of the border to London, is no exception. "It's not an easy watch, you know, but the stories are so good," she insists. "They talk about things that are so important to us all."

As with Medea in 2000, Thebans is being performed by Theatre Babel and like Medea it is based on not one Greek tragedy but a number of plays, Lochhead corrects me. Stitching together plays by Sophocles and Euripides to tell the tragic story of the House of Laius, Thebans deals with a living burial, fratricide and, ultimately, civil war. "I hope they're not solemn. I hope there's enough black irony in them," says Lochhead, laughing - something she seems to do quite a lot.

Lochhead comes across as shy but friendly, most animated when she's talking about her work. When I arrive she is scurrying around her flat, busily clearing away vases of dead flowers from the coffee table ("not very good feng shui") and apologising for the mess, though it's hardly a case for TV domestos dollies Kim and Aggie. "We should get a cleaner really. There never seems time to do it properly ourselves," she sighs.

A few minutes later, sitting at the huge, corner window of her third-floor Glasgow flat, it becomes obvious where she finds at least some of her inspiration. "I do like looking out at people's lives," she admits, the amusement showing in her eyes. "There's a good lookout from here."

But Lochhead isn't just concerned with the smaller aspects of human life. Her real talent is being able to pinpoint the detail within the broader picture. "I was just getting going on Thebans when September 11 happened," she says. "The play refers to a city where people are waiting for a war to start. There's also a woman trying to persuade her two sons not to get into a war and I think that's something you couldn't not relate to, you know."

For Lochhead herself the real battle was getting the play written. "I didn't exactly feel suicidal, that's a bit of an exaggeration, but I did feel really terrible, " she says. "I was stuck. I'd got so far and I'd done one bit that I really liked but then I got really stuck. It always happens. I always go through bad bits when I'm doing a play but this felt more stuck than I've ever been."

It was an understandably painstaking process combining two of Sophocles' three Oedipus plays with parts of Euripides' The Phoenician Women - and also having to refer back through the vast catalogue of work that other people had done on the subject. True to form, to get through the frustration, Lochhead says she focused on the parts of the story that talked about real human dilemmas. "It did make me despair of human beings. We don't seem to have changed that much," she sighs.

When I remind her that she has been described as Scotland's greatest living dramatist (a quote from the Fringe programme), she snorts with amusement that "Scotland must be in a bad way, then. I was just very lucky in that when I started to write there was a hunger for the female voice, there really was."

Although Lochhead had previously branched out from writing original material to adapting Molière, her decision to work on classical mythology five or six years ago was a new direction. "I've always loved these big Greek stories, right from when I was a tiny wee girl and my mum and dad used to read me Nathaniel Hawthorn's Tanglewood Tales. But, as far as working on them went, when Graham MacLaren approached me to work on Medea, I didn't know if I had anything to give to it or not."

Now Thebans is finished, Lochhead is going back to comedy. "I did a comedy, Miseryguts, in between Medea and Thebans and I took a couple of months off the Greeks at a certain point towards the end of last year to get going on a romantic comedy about love second time around. I'm terrible. I just go for the clichés you know."

Not that she sees it as light relief. "Writing a comedy does your head in," she admits. "You don't necessarily laugh like mad while you're doing it. You get quite a lot of laughs when you're working on tragedies, I think, because you have to, but my husband always says I'm worse when I'm doing a comedy. He gets quite used to going out and getting fish and chips."

'Thebans' is at The Assembly Rooms (0131-226 2428). Liz Lochhead is reading poetry at the Book Festival today at 1.30pm (0131-624 5050)