Alex Turner has split his trousers. We are backstage at De Montfort Hall in Leicester, and he’s holding them up so that I can see the gaping hole in the bottom. They split a few hours before, during a performance by the Last Shadow Puppets – the side-project of the Arctic Monkeys frontman with the Liverpool rocker Miles Kane – but Turner took it in his stride.

“I quietly backed off and changed between songs,” he says, sipping tequila and lime from a plastic cup. “I don’t think anyone noticed.”

Kane, an old friend of Turner, as well as his musical partner in crime, grins before recalling an old onstage wardrobe malfunction of his own, “where me trousers tore so I just started ripping them off. I forgot I was wearing a pair of leopard skin briefs that I bought for a joke.” So what did he do? He shrugs. “I let it all hang out.”

“Everything you need to know about this band ” says Turner, “can be summed up by our trousers.”

While the multimillion selling indie rockers Arctic Monkeys are on hiatus – guitarist Jamie Cook and bassist Nick O’Malley are raising young families; drummer Matt Helders is touring with Iggy Pop – Turner uses the Last Shadow Puppets to indulge his taste for the more lush and baroque edges of pop. Their debut album, The Age of the Understatement, went to number one and was nominated for a Mercury Prize in 2008. The belated follow-up, Everything You’ve Come to Expect, adds a psychedelic weirdness and sharper contemporary edge to their melodramatic harmonies.