So what is it?
A Bentley Continental V8 with a little extra. This is good news: since the arrival of the second-gen GT in 2012, the ‘base' 4.0-litre V8 has been our pick of the engines over the more powerful 6.0-litre W12.
But this V8 S, says Bentley, is a car pitched at V8 owners ‘who want more'.
What do I get for my extra money?
More powerrrr. 16kW more, to be precise, taking the twin-turbo V8's output to 389kW and cutting the 0-100 time to 4.5 seconds, the same as the regular W12. V-max? 309km/h. Sufficient.
Torque is up, too, from 660Nm to 680Nm, the whole lot on tap from 1700rpm right the way through to 6000rpm. Such grunt reaches all four wheels through an eight-speed ZF auto recalibrated to hold onto the gears for longer.
So it's thirstier, right?
No. Economy and emissions remain the same as the standard GT V8 (10.6L/100km combined, 246g/km CO2), thanks in part to the V8's cylinder de-activation system, in which four cylinders are turned off under light throttle ‘cruising' conditions, the full eight coming on song when your inner Stig takes control.
Let me guess: it's lower, stiffer, pointier?
Correct. Bentley has dropped the GT's sports suspension by 10mm, increased the spring rates (up 45 per cent on the front, 33 per cent on the rear), revised the damping, stiffened the bushes by 70 per cent and rear anti-roll bar by 54 per cent, recalibrated the steering for ‘improved precision and feedback' and loosened up the stability control to allow for ‘increased wheel slip at higher speed'.
So how do I tell it's not a cheapskate standard Conti V8?
Externally, the V8S has a more aggressive front splitter, side sills and rear diffuser finished in Beluga gloss black. Check the wheels, too: our test car was fitted with the optional 21-inch alloys wrapped around the largest carbon ceramic brake discs ever fitted to a production car (420mm front, 356mm rear).
And on the inside?
Inside the V8 S it's business as usual as you drop into what is one of the very finest interiors in the automotive world and surround yourself with quilted perforated leather, knurled aluminium dials and piano black surfaces all finished with a world-class build quality and millimetric accuracy that more than justifies the price of admission.
So what's it like to drive?
If you're taking it easy, very... Continental. The S has lost none of the GT's ability to devour huge distances while cosseting and relaxing the driver: drop the gearbox into D and this four-seater will cheerily burble across any continent you choose to point it at, with that dismissive poise that has cemented the Conti such a mighty GT car.
But the S is supposed to be for those ‘who want more' and it delivers. Drop the 'box into ‘S', gun the throttle and the V8 S rides its wave of torque all the way to 6000rpm, building speed in a way that no car weighing over 2200kg should, the optional sports exhaust serving up a very British baritone soundtrack.
Once you've re-calibrated to the fact that your GT has transformed into something altogether more menacing, you can dig into the staggering grip that the AWD GT can deliver. Dial the active damping up to Sport mode and the V8 S does a mighty fair impression of eliminating body roll, flowing through corners on a tidal bore of torque, grip and noise. The revised steering is more precise while the brakes remain face-bendingly effective, time after time.
Are you telling me the Conti's become a Lotus Exige?
No. While the poise and body control of the V8 S are both impressive and not a little unsettling, you remain acutely aware that this is a car that is piledriving physics out of its way. But if you want Exige reactions, buy an Exige: it's that seemingly unstoppable solidity that differentiates the Continental from the crowd, that makes it a Bentley.
So should I buy one?
If you've 400 grand to spend on a very fast GT, then yes, yes, yes. True, the standard Continental W12 offers more power for slightly less cash, but the V8 S is cleverer than that. It's a car concerned with the detail rather than merely the headline figures, and all the better for it.