Johnny Hallyday live at the Albert Hall

The warm-up act is a brassy blonde in a fondant-pink dress with a belief that she sounds like Amy Winehouse. Simeon, The Only Person Who Would Come With Me To This, says she got the verses of Back to Black mixed up.

‘I wonder if she’s quite famous in France,’ he says.

Johnny loves the audience and is loved in return. Especially by the gangly Frenchman in front of us who shimmies and punches the air. He works in the veterinary laboratory of an equestrian centre. Simeon’s going to make him big on YouTube.

Our seats are very high up but Simeon says he doesn't mind; he was in the Paras.

There are three large autocues in front of Johnny. ‘Johnny does karaoke,’ says Simeon.

‘That riff is plagiarised from Eric Clapton’s Crossroads. You've got to hand it to him, he knocks the socks off Engelbert Humperdinck, know what I mean?’

Johnny gets down on the floor with the mike stand. ‘So French,’ gurgles Simeon. ‘He’s giving it a dry shag.’

There are three backing singers. ‘Look at the knockers on that one,’ says Simeon. ‘They're huge.’

From the arena, long white arms wave towards Jonny like sea anemones and stiffen at his touch.

‘Is he touching your heart?’ asks Simeon.

‘No,’ I say.

‘Mine neither.’

But he's a great entertainer.  'He doesn't waste time in a power ballad. Goes straight from nought to sixty,' says Simeon, miming hanging himself. 

‘Vous êtes chaud ce soir!’ Johnny keeps saying to his enraptured fans. Men and women cry 'Johnny! Je t'aime!' Most of the men are in shirtsleeves.

Johnny sits down and reminisces about Elvis, Eddie Cochrane and the first time he went to Nashville, in 1962. He is pretend-edgy but genial. Then back on his feet.

Simeon says, ‘This is direct plagiarism of Credence Clearwater Revival’s Fortunate Son. How he gets away with it I don’t know.’

The concert ends bang on eleven. It's raining. I suggest we visit some ex-Occupy squatters in The Cross Keys off Cheyne Walk, Chelsea’s oldest pub, with memories of Bob Marley, Dylan Thomas and the Rolling Stones. It’s now boarded up: the owner wants to convert it into a mansion with a basement pool and flog it. Locals want it to remain a pub.

Seconds after we arrive in Simeon’s car, a police car and a meat wagon draw up. There is already a sinister black Range Rover with tinted windows outside.

I ring someone inside. He says the Range Rover belongs to the owner, who’d rather not go to court for an eviction order; he’s trying to lure them out by offering to leave a bag of cash in the middle of the road. They are staying put. In the store room they found a five-kilo block of chocolate which they chopped up with an axe.

We sit in the car with the windscreen wipers on, watching the police watching the pub. 

PS That was in 2012. It's still a pub.