Paul Heaton Presents The 8th, Barbican, London

“You looked confused at some points,” amiably admits Paul Heaton after overseeing his confusing and long-winded soul opera, The 8th.

The bold musical-theatre piece, which was unveiled at last year’s Manchester International Festival and is billed as “one of the longest pop songs ever”, is not the former Housemartin singer’s most soothing [happy] hour. The wrathful morality tale, which takes up the first half of this challenging concert, examines society’s wicked ways via the vehicle of the seven deadly sins, plus one more: gossip.

Each sin is provided with a different singer, so Cherry Ghost’s Simon Aldred gently prosthelytizes about greed and country singer Mike Greaves tackles pride. Meanwhile, a convincing Reg E Carthy (who played the political snake Norman Wilson in The Wire) muscularly delivers, in a fire-and-brimstone tone, Che Walker’s deranged narrative about a terrible sinner who commits a senseless murder. He sermonizes about “the implacable wrath in my heart”, and how’s he haunted by his victim’s “strawberry-type birthmark”.

It’s not a pretty spectacle. In fact, in parts, it’s a hectoring, jarring, humourless experience, peppered by an unpleasant, often blinding light show. Occasionally, this felt like an earnest sixth form production or, worse, a piece by The League of Gentlemen’s Legs Akimbo theatre company. The few highlights include the Beautiful South’s Jacqui Abbott’s honey-coated vocals on envy, Yvonne Shelton’s robust, gospel-infused take on sloth and Wayne Gidden's satisfying soul vocals on lust. Gluttony was performed by Los Campesinos!’s Gareth David, who bears an uncanny resemblance to Heaton. Is narcissism the ninth sin?

And where’s Heaton himself in all this? Well, in the background, until the 50-year-old pops up to perform the eighth sin in his sweet, mellifluous voice.

Heaton, along with Gruff Rhys, Billy Bragg and Neil Hannon, is one of Britain’s more likeable and cerebral lyricists, but this grand, operatic statement on the nation was an elaborate mess. Thankfully, for the second half we’ve been promised some “hits”. We get a few, but not a lot. Perversely he shuns the best of his pleasantly acerbic back catalogue – songs such as “Need a Little Time”, “Song for Whoever” and “Rotterdam” – and more bafflingly still he doesn’t actually sing on the majority of the chosen few, preferring to drolly orchestrate proceedings instead.

However, Gidden does supply a terrific version of the early Beautiful South track “Dumb”, Heaton and Abbott combine beautifully on The Housemartins’ exquisite “Build” and the final number, “Me and The Farmer”, finally brings the patient crowd to their feet. It’s a rousing end to a head-scratching night.