Gingerly we climb into the car. First thing you see through the cabin door are the elegantly simple seats in saddle leather, reminiscent of those from the original E-type, whose beauty and simplicity has stayed with us for 50 years.
There is brightwork, but the effect is simplicity: a generously proportioned pair of round dials ahead, a high centre console running right through the car which, fascinatingly, can turn itself into a screen, a louvred light shade above that plays patterns on the lower interior, and a simple raked fascia with a metal trim-piece at its trailing edge, with JAGUAR embossed above the console.
The essential "volumes" of the interior are as they might be in production, says Jaguar advanced design chief Julian Thomson, who is proud of what his team achieved, but the colour and trim are, in essence, experiments.
The car may look slick, but the crudity of its under-bits become instantly into focus as we begin to roll. Prototypes are usually like that. Before we go, an engineer lurking in the rear selects Drive with a tommy-bar mysteriously inserted in a hole in the console.
The car growls forward with a will, propelled too well by its 3.0-litre supercharged engine as used in the XF and XJ, but how strange to drive a Jag without an "engineered" exhaust note. It's too loud, and somewhere along the pipe, the exhaust is blowing. The suspension reacts alarmingly to the most modest bumps - these are 23-inch wheels, chosen for visual impact, not stability - and there is some disconcerting clanking from the transmission on the overrun.
Oddly, the steering feels pretty good. I briefly wonder why, then remember Graham Wilkins has confirmed this car's use of double wishbone front suspension (deemed better for precision than MacPherson struts) because it allows the low bonnet line the designers seek, and the superior steering and ride the engineers know a compact Jaguar needs.
Now it's time to pull up and let the next bloke have his go. I doubt we have hit 40mph, and there is more chuntering from the brakes as we pull up. The ghostly rear-riding engineer again does his stuff with the tommy bar and all forward motion ceases. We alight, and because we're in a Jaguar with a feet-out driving position I almost fall out of the car, forgetting that its H-point is a good 10cm higher than anything else the company makes.