Where could be more appropriate to see the story of Caligula, Rome’s most notorious emperor/self-proclaimed God, than in the Coliseum! Its purple SPQR livery made the opening to this performance all the more striking as Caligula, dishevelled, unhinged and not a little scary, crept on stage through the curtain in dead silence. So the decidedly menacing tone of the opera was set before the curtain had even been raised or a sound heard. When the curtain rises we see his sister collapse, dead, and he releases a primal scream to spark up the orchestra.

All the action takes place in the terrace of a sports stadium. A set which is practically versatile, visually striking and evocative of the rallies of dictatorial regimes – as well as a tawdry capitalist “plastic” aesthetic helped by the appearance in the stands of Mickey Mouse, Kermit the Frog, high-kick dancers, beauty queens and so on, all appearing without mention, sitting in the stands for a while and then disappearing again.

The first two acts chart Caligula’s decline into madness following the death of his sister (and also lover) Drusilla. He is beside himself, and in his loneliness he has a realisation that life itself is meaningless and pointless. So he begins a reign of unbridled terror, passing ridiculous laws and punishing ‘transgressors’ with death. Peter Coleman-Wright is entrancing as Caligula – his acting is superb, and he gives every line menace and communicates only in derision and contempt.

Glanert’s music allows few soaring moments for the singers: the majority of the singing is relatively simple melodic lines and arias are bitty and fairly short-lived. What marks out Glanert’s score is its perfect dramatic weighting and timing, its continuous momentum, and his deft orchestration. I could happily do without the amplified heartbeat and the penetrating horror-film organ chords (these were inexplicably incongruous with his otherwise considered and stylish touch). The structure highlights the quality of the text, adapted from Albert Camus’ 1930s version of the story and translated into English here by Amanda Holden. Completed in 2006 and using decidedly contemporary musical language, this feels like classical opera – it is in fact very traditional in form, and better for it.

Ending the first two acts and leading to the interval was an incredibly uncomfortable scene where Caligula invites himself to dine with his “ministers” after eavesdropping on their plotting against him. Over dinner he rapes a senator’s wife and gets his servant Helicon (countertenor Christopher Ainslie) to force-feed poison to another of his terrified entourage – Ainslie was terrific as Helicon, the dedicated servant who seems to understand Caligula and even sympathise. The dinner scene was a fantastic climax, featuring a delicious trio between Caligula, his wife Caesonia (Yvonne Howard) and poet Scipio (Carolyne Dobbin) supported delicately by vibraphone and strings. The music is tortured, reflecting all three characters’ unhappiness. By the end of the scene Caligula is left alone in the aftermath of his violence except for the naked spectre of Drusilla (present on stage throughout almost the whole piece) and the curtain falls.

Yvonne Howard as Caesonia presented this thoroughly complex character with aplomb; her voice is capable of both power and delicacy, both of which are well exploited in her rich and satisfying part. Inexplicably devoted to her husband, she eventually allows him to strangle her to death.

While the first two acts chart Caligula’s decline into madness, the third is him wallowing in depravity. The set now feels dreamlike; in its hyper-reality the action seems to take place in the crazed mind of Caligula himself. Drusilla, whose nudity seemed pointless and therefore irritating in the first two acts, was now body-painted from head to toe in the spangliest of silvers, and Caligula appears in full drag (as the Goddess Venus no less). He appears through a silver, striped curtain to a stage he has set up for himself for all to worship him and bring gifts (“no gift is too small, so long as it’s valuable”). The bass aria/duet for Caligula and Cherea was the highlight of the show, in which Caligula gains absolute power over Cherea by unearthing his plot to assassinate him then burning the evidence and declining to execute him. Pavlo Hunka as Cherea has a rich bass and the singing is sensitively supported by Ryan Wigglesworth and the ENO orchestra – responding to every nuance in the beautiful melodic lines.

The inevitable march toward Caligula’s death in the final scene did drag a little – the first time that the dramatic momentum waned even a slight bit – but when this death came the music was dramatic, saving the biggest fortissimo for the final few moments and ending (as it had begun) with Caligula’s primal scream brought a close on two hours very well spent. There are still opportunities to see this technically solid, classically proportioned and excellently performed opera – which I thoroughly recommend you do.