I do have to keep reminding myself as I tool along this particular stretch of highway at the wheel of a GS350 that I am driving a Lexus. “Just look down at the emblem on the steering wheel James,” you may well say. True, and there’s plenty of other Lexus-esque characteristics adorning the interior to remind me. But still there’s something, let’s say, out of character.

For example, as you would expect from any Lexus, the GS350’s got a well-made instrument panel, high quality upholstery and enough legroom to keep even the mightiest of charley horses reigned in. Plus comfortable seats and an (eventually) easy-to-use infotainment system that allow the clicks to sprint past effortlessly.

But how do we explain the pseudo-bucket seats, the F-Sport monikers on the dash, and the – shock, horror – Sport+ option? In a Lexus. A brand long-since synonymous with luxury and comfort. Its akin to rolling up the sleeve of a finely stitched tuxedo to show off your tattoo.

We see a similar game being played on the outside. Certainly the GS350 is a handsome beast, all sharp edges, sleek contours and sweeping roofline. But there are aggressively designed air intakes too, hunched shoulders and ripped bonnet lines. Good grief, are those wheel arches subtly flared?!

The best though is saved for the drive itself. With a 3.5l V6 lashed securely under the bonnet, there’s poke and lots of it. Even in Eco mode, where lethargy is traditionally supposed to take charge over boisterousness. Accordingly the engine will keep pulling as you inch towards the redline. The steering is agile, good heft and feel for the road delivering confidence to the driver in spades. Tap the brakes, and good balance means speed is scrubbed just as eagerly as it was gained, though not overly abruptly. It’s all very easy.

Then I spin the drive select dial a couple of flicks to select S+, and my word, do my eyes widen quickly. All 312hp are suddenly alert, focused, and ready to bite. Tap the accelerator and power comes matter-of-factly, becoming more abrupt should gravity take control of your right foot.

There’s a bit of weight to the nose, meaning the car can wash wide, but you’re soon too busy fighting the rear back into line to pay much attention. Reign in your enthusiasm with the go-faster pedal a touch, and at the next corner the rears will once again light up, gliding rather than sliding out of line this time, daring you to counter steer and hold the slide. And by dare, I mean scream.

Another hour down and crankandpiston’s time with the GS350 is up. The test has been very thorough, several prominent tyre marks on the road confirming this. My lairy experiments haven’t blown all the cobwebs away though. True, this is a Lexus offering both comfort and sophistication, but with the flick of a dial can strike back with furious anger.

So before you jump behind the wheel, you should ask yourself one question: would you rather spend the afternoon with Dr Jeckyll or Mr Hyde?

For more epic shots of the Lexus GS350 F-Sport, check out our Gallery.