The Emperor of Atlantis, Kilmainham Gaol Museum, Dublin

Written for performance in the Nazis' "paradise ghetto" of Terezin, Ullmann's The Emperor of Atlantis is something of a problem piece. It was written in 1943, within months of the murder of Ullmann's librettist, Petr Kien, in Auschwitz. Ullmann himself was killed there the following year. Whatever our duty to works written so close to the abyss, as perspectives lengthen the questions of the work's artistic worth and dramatic viability become more pressing.

The plot, in which Death goes on strike and redemption is achieved only when Emperor Overall agrees to be the first victim of a new era, is, of course, heavily allegorical, not just of the political horrors that brought about obscenities such as Terezin and Auschwitz, but more broadly of the hideous inevitabilities into which a society gone mad locks itself. Ullmann matched Kien's metaphorical libretto – given in Aaron Kramer's brilliant, provocative English translation – with a wide-ranging score. Though a one-time pupil of Schoenberg, Ullmann was far from the cutting edge of Thirties Modernism; at its most extreme the score's affinities are with the Berg of Wozzeck. The complex montage of Kien's libretto is paralleled by a tissue of allusions ranging from Mahler and Mendelssohn to Bach, the blues and popular dance idioms, the whole framed by the "fate" motif of Suk's "Asrael" Symphony, well known to early-20th-century Czechs as a harbinger of mourning.

The prison-camp audience for which the work was conceived was perhaps one of the most intellectually able and culturally aware assembled in the 20th century. In difficult times, allusion becomes a common currency, but there is a danger that a score born of this background can lose its force for a later generation. The fact that it didn't on this occasion owes much to the conducting of John Page. Leading a motley ensemble of the instruments available in Terezin – ranging from banjo continuo, through strings to alto sax – Page traced a path through Ullmann's score that forged connection rather than disjunction: the duet between Girl and Soldier, sung with sweet poignancy by Emer McGilloway and Eamonn Mulhall, was disturbingly beautiful, as was the final chorale.

The setting of the internal court of Kilmainham Gaol – redolent of the suffering of the 1916 insurrectionists – proved a superb natural auditorium. Moreover, the court brought pace and energy to John Fulljames's magnificent production, its resonant spaces strengthening memorable ensemble performances from Omar Ebrahim's Death, Declan Kelly's Harlequin and Emer McGilloway's Drummer Girl. As convincing was the Emperor himself, isolated to a remote podium in a morass of his own making and projected with wonderfully calculated neurosis by Geoffrey Dolton. In short, every element of Opera Theatre Company's realisation of the elusive, allusive work spoke with triumphant coherence to the audience of today.