Nero

I've been waiting to see Nero for years. I remember getting hold of an early workshop recording featuring Idina Menzel and Lea Michele, back when Wicked and Spring Awakening occupied most of my musical theatre world. I saw Spring Awakening at the Lyric Hammersmith, and the way Duncan Sheik's contemporary score worked with its nineteenth century setting has stayed with me. Ancient Rome seemed a wonderfully unlikely next destination for Sheik and Steven Sater. Following Sheik's death in September, hearing Sater speak about their long partnership before the show gave the evening a particular sadness.

Southwark Playhouse has given me plenty to enjoy over the years, and Georgia Lowe's deep red curtain and enormous illuminated NERO sign promised something showy. A balcony runs above the stage, with a ladder connecting the levels. The opening chants turn us into Nero's admirers before Andrew Barth Feldman appears above us, whipping up cheers like a glam rock frontman. I liked the cheek of being asked to applaud him before we'd seen what he was capable of.

Feldman is excellent at being impossible. His Nero is a spoilt child with an empire at his disposal, quick to sulk, flare up or demand attention, and I believed every tantrum. His ego grows until everyone around him seems to exist for his amusement, although Agrippina and Poppea know exactly how to steer him. Feldman catches that contradiction: he is desperate to rule, yet surprisingly easy to manipulate. The singing is terrific, but I was more taken with his acting, particularly the switches between childish affection and casual cruelty.

His appearance grows more outlandish alongside his ego. Pink feathers, the pink bra, glittered cheeks, a gold wig, an extravagant gold cloak and an enormous green fur jacket were among my favourite touches. It made me think of Hedwig and the Angry Inch, and I was all for it. I kept thinking how effective it might be if Nero were the one flamboyant oddity in an otherwise more formally played court. Let the emperor grow ridiculous while those around him have to treat his whims as law.

Sally Dexter almost supplies that contrasting world on her own. With the white hair and stern bearing, her Agrippina looks as though she could be plotting her next move in Game of Thrones, and Dexter delivers her lines with Shakespearean assurance. She can be calculating and almost tender towards Nero in the same scene, which makes their growing possessiveness particularly uncomfortable. I never doubted they were mother and son, despite their very different performance styles. Even the enormous white sunglasses during her exile feel like a flash of personality rather than a change of character. I missed Dexter after Agrippina's death; Nero's reaction worked, but I wanted to see her play that final confrontation.

Rhianne-Louise McCaulsky was another reason I wanted to see this, having watched her as Rachel Marron in The Bodyguard in Slovenia. Her Poppea is ambitious and vocally commanding, and the sparkling silver costume suits her perfectly. Her chemistry with Feldman gives the relationship real force, which makes the violence towards her while pregnant all the harder to watch. Waylon Jacobs gives Tigellinus a difficult balancing act: once aligned with Agrippina, he pledges himself to Nero even as the emperor becomes involved with his wife. I was interested in those compromises and how far people would bend to stay close to power. Stephen Carlile gives Seneca welcome dry humour, Timo Tatzber has a lovely voice as Britannicus, and Nabi Brown is an appealing Octavia who deserved more time on stage.

The score is an easy listen, and I mean that positively. The Winter Wind gave me flashes of Spring Awakening, particularly in its lyrical phrasing, and the five live musicians sound lovely, with the harp especially noticeable. I liked the joke of introducing the band as figures from antiquity, too. Nero's Mind lets Feldman revel in the theatricality, while Golder by the Day, A Double Dip of Darkness and Quelle Surprise all have their own quirks. I came away wanting to hear The Winter Wind and the finale, Troy Is Burning, Love, again.

Robbie Butler's lighting makes fine use of fiery reds and sharp white beams, while James Cousins' choreography gives the ensemble numbers energy. One of my favourite visual moments was the mirror reveal, when we could see the action from behind as well as in front. Those choices have a confidence that some of the comic props lack. The toy pistols struck me as an odd fit with the courtly seriousness elsewhere. I had no problem with Nero's absurd wardrobe, but the rules of the world surrounding him seemed to change from scene to scene.

That uncertainty affects Sater's book and Lindsay Posner's staging too. I wasn't troubled by the difficult subject matter itself; the Roman court is hardly somewhere to expect gentle behaviour. I did want clearer reasons for some decisions, particularly Nero's order for Seneca to take his own life. The attack on the pregnant Poppea is upsetting, yet other terrible events pass without quite the same weight. I enjoyed the ghostly tango, even as Ghost in a Box seemed to interrupt a different sort of tragedy. At two and a half hours, the musical has time to join these pieces more convincingly; at present it moves too abruptly between political drama and broad comedy.

I'm glad I finally saw Nero. Feldman is terrific, Dexter had me completely, and there is plenty of Sheik's music I'd happily hear again. I would return to a revised version, because I like how far the production is prepared to go. Its outrageous humour, striking costumes and darker moments occasionally come together brilliantly, offering a glimpse of what this musical could become. I wouldn't want it to lose that eccentricity, but the surrounding characters need a more consistent world. Feldman knows exactly who his Nero is, while the musical around him is still deciding.