The temperature's rising, the traffic lights are on red and my passenger, located somewhere behind me in the far reaches of the car, is late for his business meeting.
It's the perfect test for my long-wheelbase Rolls-Royce Phantom. If it cannot perform here, relaxing my passenger with its opulence and air-cooled comfort, it has failed as a luxury limo. More to the point, if I can't perform here, I've failed as a chauffeur.
You see, I'm learning to be one; a student of Abbass Zadeh, founder of AZ Luxe, whose company motto is: 'Arrive in luxury, depart in style.' Today, I'll test that claim – hopefully, not to destruction.
At least I won't be able to blame my teacher. Abbass, as he's known, knows his business and he's as entrepreneurial as any of his customers.
"I financed my new company with the proceeds from selling my house," he tells me. "One of my first cars was the Phantom. It's the former company car of Rolls Royce CEO Torsten Müller-Ötvös and is very special."
It has since been joined by a Rolls-Royce Wraith, two Mercedes V-Classes and three S-Classes, two Lamborghinis, including a Huracán Performante, and a Mercedes-AMG GT Roadster. With the exception of the Phantom, all are new cars. His house must have been very big.
To get a feel for chauffeuring, Abbass says that this afternoon, I can take one of his customers to a meeting in the Phantom.
"He usually has the S-Class but I offered him a free upgrade," Abbass explains.
First, however, I must study the company bible, a guide covering everything from the required colour of his drivers' ties (black or navy) to matters of etiquette such as not asking for a selfie with your passenger.
Abbass now leads the way to thenearby Berkeley Square NCP, central London, where the Phantom resides. Against the grubby walls, and illuminated by the stark fluorescent lighting, it looks superb. It's easy to see why someone might consider £156 an hour (minimum booking, four hours) for its use money well spent.
"A few dos and don'ts," he says. "Never walk in front of the Spirit of Ecstasy – always behind the car. Greet your passenger with a smile and a steady gaze, and open the door with your right hand, your left behind your back ready to take their bags.
"Once they're in the car, point out the heating controls and show them how the TV screens pull out. Don't close the door but allow the motor to pull it shut.
"From the driver's seat, confirm your passenger's destination, check if they have a preferred route and give them an ETA. Check they're happy with the cabin temperature, and if they'd like the radio on, ask which station they would prefer."
With Abbass in the passenger seat, I slip behind the Phantom's large steering wheel, press the power button and ease the car out of the NCP towards Park Lane.
Abbass tells me to allow plenty of space behind taxis so that if they suddenly stop for a fare, we can pull out and continue uninterrupted. Turning at junctions is best done by feeding generous amounts of wheel through the hands, rather than short, fussy fingerfuls, he advises.
The Phantom's braking is magical – momentum simply evaporates. Accelerating well is the hard thing. At no time must your passengers be pushed back into their seat. It takes practice.
Abbass insists his drivers are at their appointments 15 minutes early. Accordingly, I steer the Phantom into a bay close to my customer's agreed pick-up with time to spare and wait by the passenger door. All too soon, he's at the car.
Abbass's bible goes out of the window as, staring at the ground, I mumble "Sir", begin to open the door with my left hand – an almost impossible feat – and all but bundle him into the back seat, before slamming the door closed and nipping past the Spirit of Ecstasy to the driver's seat.
Once installed, I lurch off towards a T-junction before remembering to ask where my passenger would like to go. Kensington High Street? Great: I know that.
"Too hot? Radio too loud?" I blurt out.
"I'm just on the phone," he replies. Some people... I practise some textbook driving: hands at 10-to-two, straight back, smooth braking and acceleration...
"I'm going to be late," says my passenger. Personally, given the traffic, I'd have taken the tube. Still, I can see why, with Tchaikovsky and Mozart playing on Classic FM – separated by an ad for a shingles treatment – the idea of motoring in comfort past curious bystanders holds more appeal.
We arrive at my passenger's destination. "Pick me up in 10 minutes, John," he says as he heads off.
That should give me time to turn the Phantom around and be on the right side of the road for the pick-up. I've noticed how cars, even black cabs, stop to let the Rolls through. Can't see them doing that for a Mercedes V-Class. He's back. This time, I'm ready. A confident hello, left hand behind back, right hand opens door, allow ample time for passenger to get comfortable and door to pull shut, walk behind car to driver's seat, establish temperature is okay and radio at the desired volume, confirm destination and we're away.
"How was your meeting, sir," I enquire, as the Rolls joins the traffic.
"Very good, John, thank you," he replies. He says nothing more but that's no problem: I've established that he wishes to be left in peace.
But for a moment when I forget to follow my passenger's advice to take a left into Sussex Gardens to avoid the crush at Marble Arch, I feel the return journey is much better.
"Nice ride," he says as he emerges from the Phantom. "A pity you forgot to go via Sussex Gardens."
I bark out a laugh and punch him matily on the arm. Abbass shoots me a critical look. Unfortunately, there's worse to come, at least for him. A few days later, a penalty charge notice lands on his desk. I'd dropped off my passenger in a suspended parking bay. According to his manual, I, as the driver, must pay it. Instead, Abbass, being a thoroughly decent gent, does. Sorry, mate.
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