"C'mon," says Seal, holding back the first verse of his signature tune Killer until the audience is clapping from front row to back. Then he leaps into the crowd, singing from the aisles as flashbulbs pop and people grin in disbelief, making the a capella ending as incongruous as it is eerie: "It's the loneliness that's the killer."

It is 22 years since the acid house crossover hit with Adamski made Seal a household name, and this two-hour marathon reflects a sometimes scattergun career. There are uptempo rockers (If I'm Any Closer), knowing dance stompers (Loaded), personal and insightful musings on mortality (Prayer for the Dying), acoustic blues numbers and even a weird monologue about nightmares accompanied by Jimi Hendrix-style guitars.

With his black top, gym-toned physique, big boots and Day-Glo yellow nail varnish, the singer – born in London of Nigerian and Brazilian heritage – remains a natural pop star and waggish entertainer. "I'll sweat a bit and hopefully encourage you to do the same," he quips, as someone yells back: "Ooh, I say!"

However, at 49, the singer has travelled from rave dancer to soul man. He brings a husky sincerity to Stylistics and Al Green classics from last year's album of songs he loved as a teenager, Soul 2, while his best originals pivot between agony and ecstacy. Secret, a lovely ode to parenthood, gains a certain frisson following his recent divorce from Heidi Klum.

The material can waver, but he never stops giving everything of himself, perhaps as a way of working through his troubles. A speech thanking his audience for sticking with him sounds candid not cliched. He pours emotion into Crazy's "We're never gonna survive unless we get a little crazy," refrain, then leaps into the audience as they do indeed go a little crazy.

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