Audi’s flagship executive sedan, the A8, is nearing the end of its product cycle. It saw a minor facelift for 2015 that gave the regal full-size a tad more visual bite. Put a 2014 and 2015 A8 side by side, and you’ll notice the newer model has a slightly larger (is that possible?) and more angular grill, redesigned full-LED headlights, a more defined chin and interesting character lines that sweep from the sides of the headlights down to the front splitter. The hood has some fresh creases that are consistent with the more aggressive look.

Out back we see a recontoured derriere with thinner taillights, a metal valance around the exhaust tips and a wider trunk lid featuring a new slash of chrome.

All very subtle stuff that doesn’t really alter the overall impression of a big, stately luxury sedan that telegraphs… well, not a whole lot really. Unlike the Jag XJ or even the new Mercedes-Benz S Class, the Audi A8 seems determined to fly under the radar. No flash here. It looks nothing more than a larger, squared-off and slightly more imposing version of Audi’s lesser four-door offerings.

Oh, wait a sec. This one has an S before the 8. That means fast, right? Plus those five-spoke 21-inch wheels looks suspiciously… big. And the exhaust sounds rather serious too. It rumbles and woofs with a barrel-chested depth that signals something ominous is afoot.

Yes, we’re looking at the $128,900 2015 Audi S8 here, that, with 520 hp and 481 lb-ft squeezed from the 4.0L TFSI twin-turbo V8, runs unapologetically with the super-sedan crowd – the Mercedes-Benz S63 AMG (577 hp $156,400), Porsche Panamera Turbo (520 hp $161,500), BMW M6 Gran Coupe (560 hp $127,900) and Jaguar XJR (550 hp $119,900).

A strange breed of vehicle are these. Whether or not you can find any logic in taking what is all ready a swift and luxurious full-size sedan, then making it marginally quicker, less comfortable and whole lot more expensive, seems completely beside the point. Still, there will always be those who’ll happily pay the additional $25,700 the S8 demands over the 435 hp A8, just because anything less than the baddest “8” just won’t do.

Indeed, this velvet glove packs a wallop when pedal hits the metal. The S8 may be down on power and torque compared to its rivals, but a zero to 100 km/h dash of 4.0 seconds is mighty impressive, and it accomplishes this feat with turbine smoothness thanks to the creamy V8 and the equally slick eight-speed Tiptronic automatic transmission that swaps cogs with near imperceptibility. A truly epic drivetrain.

The S8 is the quintessential Autobahn hero, happiest cocooning its occupants while gobbling up vast chunks of blacktop at superhero speeds. Or so I would imagine.

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