As her show-stopping aria ‘Vissi d’arte’ (‘I lived on art’) in Act 2 tells us, Tosca’s is a story of art being suddenly caught up in war. In an ITM feature the week before the run, director Oliver Mears was quoted as saying that Derry’s conflicted past, as expressed by the historical aura of some of its iconic buildings, made it the perfect place to stage an opera about the turbulence of Napoleonic Europe. Events proved him right, but not for the right reasons: a bomb-scare near the courthouse on Friday morning meant that the first act of the performance could not take place in St Columb’s cathedral as planned. Proof that peace here is, at best, in process.

This deprived the matinée audience (which included numerous schoolchildren, from both sides of the community) of what the other performances revealed to be one of the highlights of the production. Setting Act 1 in a real church (Puccini’s stage directions specify Sant’ Andrea della Valle in Rome) provided for a spectacular and musically powerful climax, with the rousing ‘Te Deum’ sung by an impressive local chorus advancing up the nave as Scarpia resolves to possess Tosca and send her lover to the gallows.

All was not lost – in fact things could have been a lot worse. Although the disruption caused visible tension among the creative team (the local audience, well used to it, hardly batted an eyelid), the much-talked-about decision to use three separate sites for the three acts turned out to have not only artistic but also practical advantages. The performance simply began, only a little late, in the Guildhall, also the venue for Act 2. It even has its own organ, so the ‘Te Deum’ was still properly grandiose. Scarpia’s line near the end of it, "Tosca, you make me forget God!", one of many distinguishing features of Carey Jones’s menacing performance, was as hair-raising as it’s meant to be.

The rest of Act 1 was mixed: Jesús León’s Cavaradossi was vocally sweet, but a little light for the role, more bel canto than Puccini. Also, he never knew quite how to handle his jealous lover, several times just letting his arms fall impatiently to his sides when the libretto makes it clear he is well used to this sort of carrying-on – even if this time he has an escaped political prisoner hiding out in the church where he is painting. Lee Bisset as the impulsive diva was more convincing; as a couple they were remarkably believable. When the tenor is himself in prison in Act 3, remembering Tosca (‘And the stars were shining’, an affecting but oddly distant rendition of his big aria), his words are not about the standard operatic abstractions, but rather the recollection of undressing her – yet it’s by no means every Cavaradossi-Tosca pair that you can imagine actually making love.

In Act 2, when Scarpia has Cavaradossi tortured within Tosca’s hearing in order to extract from her Angelotti’s whereabouts, she was credibly distraught, and sang ‘Vissi d’arte’ from a chair, as fragile and vulnerable as she was elsewhere glamorous and animated. Moments later, when he attempted to collect carnal payment for safe-passage for her and Cavaradossi and she stabbed him, she was alarmingly unhinged, laughing crazily as she dodged his flailing arms, and then morbidly fascinated by his agony. Her repeated line, "Is your blood choking you?", usually delivered as a vengeful taunt from out of reach, here had a note of genuine curiosity. She came close, almost lay on top of him, and looked at him fixedly. Tosca is, as she tells Cavaradossi in Act 3 while he prepares for what she assures him will be a fake execution, expert at dying convincingly on stage – and here there was, alongside the horror of having inflicted death, a unique opportunity to see what it really looked like.

Indeed, it was this aspect of the opera that the production revealed with most clarity: Tosca is all about representation. From Scarpia’s likening of himself to Iago to his elaborate pantomime with his henchman Spoletta (a fake execution "like we did with Count Palmieri"), and from Cavaradossi’s musings on art and life in Act 1 to his death in Act 3 (a staging of real insight, featuring an authentic-looking anni di piombo police cell and the mute execution of another prisoner during the prelude), the plot turns on the difference between what is true and what is false. Reports from the battlefield at Marengo, which arrive in Acts 1 and 2, are first false and then true.

Thankfully, those about a bomb at Derry courthouse on Friday proved false. But those about one in Omagh the following day were, tragically, true.

Cormac Newark is Senior Lecturer in Music at the University of Ulster; his book Opera in the Novel from Balzac to Proust has just come out with CUP.