Composer Viktor Ullmann wrote his opera The Emperor of Atlantis in a ghetto north of Prague and later died in Auschwitz. Opera Theatre Company's production in Kilmainham Gaol, which draws the audience into the action, could have no more appropriate setting.

"Every prison that men build is built with bricks of shame . . ."

- Oscar Wilde, The Ballad of Reading Gaol

"Faced by the question of how people could perform and compose even in the depths of hell, there were basically three attitudes among the inmates. The naïve prisoners were oblivious to their surroundings and did not absorb the full impact of their situation. They saw no reason to change their lifestyles; if they practised six hours a day before the war, they would continue to practice six hours a day in the camp. The optimists believed that the war would soon be over and that the civilised world would not allow the atrocities to continue. They would continue to practice in anticipation of their imminent liberation.

"Then there were the pessimists who said: 'We will soon be murdered; why not make the best of our lives while we can?' Thus the pessimists also continued to perform."

- Paul Kling, violinist, on Terezin concentration camp

IF the bulky grey walls of Kilmainham Gaol could talk, their tales would doubtless be pretty downbeat. In a way, perhaps, they do: visitors to the museum are invariably impressed by its sombre dignity. One way or another it is a strikingly apt setting for Opera Theatre Company's forthcoming production of The Emperor of Atlantis. Written by the Czech composer Viktor Ullmann during his incarceration at Terezin, the obscene "model ghetto" north of Prague into which the Nazis deposited almost an entire generation of Jewish artists and intellectuals, the piece was banned by the SS officer in charge of the camp for its allegedly anti-Hitler sentiments and was not performed until 1975. The OTC production will use the gaol as a set, playing the opera's four scenes at different locations in the east wing of the building, with the audience following the action - literally - as it moves from place to place.

"Hopefully we'll be able to explore ways of making the audience feel like protagonists rather than just part of an ordinary audience - that it will be something you experience rather than just watch," says the opera's director, John Fulljames. "It's easy to look at the piece and say it was written by prisoners in a Jewish ghetto; but equally, it was written for prisoners in a Jewish ghetto. It was written with a specific audience in mind - and I think helping the audience to see themselves in those shoes is going to be interesting."

Viktor Ullmann was born in the city of Teschen, then a garrison town of the Austro-Hungarian empire, on July 1st 1898. He earned a medal for bravery on the Italian front, but was sickened by the absurdity of the fighting. After the war, he studied composition with Arnold Schoenberg and in 1921 he became choirmaster at the Neuen Deutschen Theater, now the National Opera of Prague, where he worked with Alexander Von Zemlinsky. In 1942, he was arrested and interned in Terezin, where, in just two years, he produced some 22 musical compositions and 18 texts. "It was an extremely fertile time for him," says Fulljames, "perhaps because he felt his art had a new purpose - being able to compose became a tool in maintaining his dignity, maintaining his humanity. But also, he was a composer who had always had lots of other things to do - life had been very noisy. He'd been a conductor, he'd been a critic; somehow Terezin forced him to give space to the purely creative part of his life."

Though Nazi propaganda claimed it was a "paradise ghetto" and pointed to its lively programme of concerts and lectures and its relatively elaborate productions of operas, such as The Magic Flute, The Kiss and The Bartered Bride, a spell in Terezin was anything but a soft option - Pavel Haas, whose pre-war opera The Charlatan was performed at Wexford Festival Opera two years ago, wrote very little during his time there. The fact that some 20,000 inmates died during one 10-month period indicates just how bad conditions at the camp actually were.

That the score of The Emperor of Atlantis survived at all is itself something of a miracle: on October 16th, 1944, Viktor Ullmann was put on a train for transfer to Auschwitz where, two days later, he was murdered. "He always swore he wouldn't let the score leave his side," says John Fulljames. "He put it in his suitcase, but at the last minute he decided to give it to somebody else to look after for him, and they were never deported from Terezin."

Like many of the works classified by the Nazis as "entartete Musik" (degenerate music), The Emperor of Atlantis has been recorded, and given numerous performances since its world premiere in Amsterdam in 1975. The opera begins with the Emperor Overall declaring a "holy war". Death goes on strike in protest, and as the fabric of society begins to unravel, the authority of the reclusive Emperor - who communicates with the outside world via radio and telephone - is undermined by a rebellion. A girl and a soldier from opposing sides in the war fall in love. Finally, Death agrees to return to work - on condition that the Emperor should be his first victim. Dramatically, says director John Fulljames, the piece shows the influence of medieval morality plays and, in its use of a Harlequin figure, of Commedia dell'Arte; but it also prefigures the nihilism and futuristic bleakness of Beckett and of films such as Metropolis.

Fulljames is no stranger to futuristic bleakness. He studied physics at Cambridge, but has no regrets about leaving the scientific life or, as he puts it, "sitting in a darkened room with a notebook".

As an opera director he has specialised in the 20th-century repertoire, including Peter Maxwell Davies's The Martyrdom of St Magnus, Shostakovich's The Nose and James MacMillan's Parthenogenesis; he is also something of a Wagnerian, working with Moshe Leise and Patrice Caurier on their high-profile Ring Cycle in Geneva.

BUT the musical landscape of The Emperor of Atlantis is, he says, quite unique. "Imagine Kurt Weill - imagine a cabaret band, then cross it with a bit more Schoenberg and a bit of Zemlinsky. A bit more atonal than Weill normally is, and quite a lot lusher as well. It also feels rather like a Bach Passion at times, the way it mixes ensembles, solo arias and chorales - so you have a number at the end of a scene, which puts that scene in context. Bach is a big influence on the music. And Ullmann uses a lot of very formal musical forms - he uses the fugue a good deal, for example.

"But, for me, one of the amazing things about the music - and the text, as well - is the humour. Although it's a very dark subject, it's treated in an extremely light way; it was written to entertain people, after all. The point is that life is about laughter and that we're still going to laugh, no matter what happens."

The Emperor of Atlantis runs Thursday-Saturday at Kilmainham Gaol, Dublin, at 8.30 p.m. Booking on tel: 01-6708326