"I'm just a few seconds, I've got a patient in here," says Sir Paul McCartney, sticking his head through his office door.
He disappears and nervously scans the books in the waiting room-three dictionaries, a few pocket folios, a couple dozen Beatles reference books, and a surprising number of Jamie Oliver cookbooks.
Minutes later, Sir Paul reappears and leads his "patient", who turns out to be one of the many assistants in his posh, five-story office in Soho.
"Take the tablets three times a day," he jokes. "You might feel a bit drowsy at the beginning."
As he lures you in, the star starts to wiggle around in the room and talks quietly ("You're from Belfast, I thought I'd discovered that nice little accent") and set up his picture frames.
"Easy Obsession," he says. "What do you call the" obsessive-compulsive disorder. " disorder! I think it's the opposite. I think it's okay. "
All of this kerfuffle is designed to soothe you.
The most famous musician on the planet is fully aware of its impact on the lower mortals and, 56 years after Love Me Do, he is well versed in calming people's nerves before collapsing like a bouncy castle in a power outage.
You can see it in practice in his latest episode of Carpool Karaoke when the 76-year-old is besieged by fans outside his parents' home in Liverpool.
Slowly but purposefully he walks through the crowd – shakes hands, says hello, acknowledges everyone; but constantly forward until he reaches his car and slips in with one last wave.
It is a finely tuned survival tactic that emerged in the early days of the Beatles "when it started and went crazy".
"Before, we only wanted fame and we did not have one," he recalls in his office.
"Once we got fame, that was nice, then it got a little crazy, so you had crowds that attacked and grabbed you.
"What occasionally happened was that you had security guards who would growl:" Get out of the way, get out of the way! "And the crowd would get a bit aggressive.
"So we've learned to move forward and be very calm and relaxed about the need to make a crazy scene even crazier."
Incredibly, the star says he can go unnoticed in public.
Last weekend, before he played a concert at New Central's Grand Central Station, he walked around the hall filming his iPhone "just to get a feel for it" without being bothered.
And on the rare occasions when he uses public transport, he says people are often too distracted by their phones to discover it.
"When I'm on a train, I see everyone else is just looking at their screens," he says. "But I look: Oh, look, there's the London Eye, there's the Thames!"
And if a passenger looks up, they would probably go, "Oh look, there's Paul McCartney!"
"Yes," he laughs. "And sometimes they look up and they take a small picture and they sell it to the newspaper.
"And that's the price of fame."
Even so, the star seems to be in the spotlight for his sixth decade – appearing at the Cavern Club to make a surprise appearance; Participation in a Facebook Q & A with Jarvis Cocker and stroking fans in a lift.
All of these activities support a new album, Egypt Station, which has included some of Sir Paul's most insistent and immediate songs for years – from the blissful domesticity of Happy With You to the playful Come On To Me poetry about hooking a house party.
"You know, Rock & Roll, its origins are pretty funny and funny," says Sir Paul. "It should not be a serious job.
"Why we loved it was Elvis Presley, who sang Baby, Let's Play House, and he got it from the Blues singers, who were all pretty playful as well."
Come On To Me's flirty lyrics were triggered by a raging guitar riff Sir Paul had played with.
"You always start with a little guitar phrase or something," he explains. "I had the little riff that started the song, and I started thinking about parties in the 60s where you saw a good-looking girl and she smiled and you thought," Oh, is that coming or going? I got that wrong?
"Well, that does not happen these days I hurry to add! More than my life is worth it But often with songs you remember a certain event and you go back to it and you paint the picture based on that memory that's one of those. "
Other songs take on a more serious tone – like Who Cares, who addresses the brutality of Internet bullying.
"I was actually thinking about Taylor Swift and her relationship with her young fans and how it's sisterly," Sir Paul says of the origins of the song.
"And I imagined talking to one of these young fans and saying," Have you ever been bullied, are you being bullied? "
"Then I say, 'Who cares about the idiots? Who cares? Who cares? Well … I do.'
But the worst moment of the album comes despite Repeated Warnings – a hate speech about the deniers of climate change, with a lyric that could not be more current or relevant:Those who shout loudest are not always the smartest, "
"People who deny climate change … I just think it's the dumbest thing there has ever been," says the star.
"So I just wanted to make a song that talks about it and basically says," Occasionally we have a crazy captain sailing this boat, and we all bring us to the iceberg [despite] be warned, it's not a cool idea. & # 39; "
That crazy captain, could it be someone special?
"Well, I mean, it's obviously Trump, but there's plenty of it, he's not the only one."
Bond on the run
At the time of writing, Egypt Station was out to replace Eminem at the top of the charts, giving Sir Paul a 23rd number one album (including 15 with The Beatles and two with Wings).
How does he measure success now? Are there any more records?
"Success is when I like what I've done," he says. "That's the real one. If I actually think," Well, that's pretty good. & # 39;
"If it comes anywhere in a kind of chart, that's a bonus – but that's not as easy as it used to be.
"I remember one of my kids when they were little, said," Daddy, I like this song, can you please put it in the charts? "And I said," Yes, I will mine Giving the best!"
A foolproof plan for a hit single would be to write the next James Bond theme – a bombastic sequel to Live And Let's 1973. But the star has none of it.
"One is enough!" he calls, before he makes the extraordinary revelation, that "I never thought that letting live and die was a particularly good Bond theme."
When it points out that his ever-changing pomp-rock classic regularly quotes polls of the best Bond songs, Sir Paul gives in.
"Well, you see, that happened, people say, 'This is my favorite!' So I'm convinced, and now it's my favorite too.
"It was on TV the other day, and I thought, 'Oh yeah, it works great.' But I think it's enough."
He would make an exception, however, when Daniel Craig invited the Foo Fighters to sing his double-oh-swan.
"They would be really good," says Sir Paul. "I think they could handle that and then they could play me on the drums!"
Anyway, he's too busy to record new music, Bond or anything else, with a mammoth world tour starting in Canada next week and running until summer 2019 (with a gap for a much-rumored headline Glastonbury slot).
And while his contemporaries Sir Elton John and Paul Simon make farewell trips, Sir Paul can not imagine leaving the business.
"Retreating what?" He said 6 Music earlier this year – and acknowledged that he understands the impulse to move away from "the actual physical thing of travel."
"Billy Joel has a residency at Madison Square Garden, which is a nice, easy jump from his house, and I think people are starting to do a little bit more," he says.
What did he say to Joel's recent admission that he had given up publishing new music because "I could not be as good as I wanted to be and I was frustrated"?
"These things happen to you, you get disappointed with what you do [and say]"I'll never do that again." I suppose he really sulks. "
When this mood hits him – and he does – "I just go and do something different, maybe go on vacation or something and that can make you hungry again.
"But I still love what I do, I know everyone says that, but it's true, the idea of having some time to record a guitar and a noodle and find a song in it is still magical for me me, the whole idea of it.
"And I still love it when I get away from it and I have a song, so I'll do it forever."
Sir Paul McCartney's 17th solo album, Egypt Station, is now out.
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