What's the elevator pitch?Let's boil Lexus down to one word\: different. In a market dominated by the Mercedes S-Class, and populated by heavy hitters like the BMW 7 Series, Jaguar XJ and Porsche Panamera, you can't be backwards about coming forwards.The new LS 500h refines Lexus' aesthetic willfulness - there are 5000 separate elements in the 'spindle' grille - and revels in the fact that this is a defiantly Japanese product. 'Brave design' is how Lexus itself describes one of its USPs, though that's an adjective that can cut both ways depending on emphasis.Close to 30 years since the original LS 400 gave the Germans the willies, Chief Engineer Toshio Asahi notes that luxury is now about experiences rather than possessing luxury items, so Lexus has shifted from being a luxury car brand to a lifestyle brand that offers amazing experiences. Lexus doesn't have customers, it has Experiential Masters.Does it indeed. It would appear that even the most honorable Japanese automotive engineers now speak fluent marketing babble.Needless to say, the average LS Experiential Master is an enviable one of artful daily innovation, financial guile, and general self-improvement. Love those guys. But at least the new car is suffused with the sort of thinking they don't bother with so much in Stuttgart. Omotenashi, for example, which anticipates the customer's needs before they've even arisen, and elevates hospitality to an art form.Or Takumi, Lexus' in-house artisans who have a minimum of 25 years' training before being let loose on the LS's interior accoutrements, and who have their eyes tested every four months lest a stitch or seam goes awry. No pressure here. We've come a long way since the days when you got a slab of wood appliquÃ© and a push-button FM radio.The LS500h's interior certainly looks pretty cool. Does it work?Mostly, yes. When it comes to differentiation, Lexus definitely walks the walk as well talking the talk. There's detail, quality of execution, and imagination here to rival Rolls-Royce's exquisite new Phantom. Lexus has even managed to invigorate the interior real estate where door meets dashboard, creating a sense of flow that's heightened by the ambient lighting (inspired by traditional Japanese Andon lanterns) and the 'floating' arm-rests.The top-spec premier version can be ordered with Kiriko glasswork for extra dazzle, and hand-pleated inlays in the door panels that reference the Origami tradition. Props for giving it a go, although the effect is more Kowloon knock-off tailor than Cotton Club zoot suit. There's a new, smaller diameter steering wheel whose profile varies around the circumference for satisfying tactility. Slender rotary heating dials and a beautiful power on/off and volume knob confirm that some things are simply better analogue. Again, similar to the Phantom. Or, say, The Damned's 'New Rose' on seven inch vinyl.They'll also probably still be working in 2037, while the rest of it has gone on the blink.You may have a point. On which note, the LS 500 has an Optitron main instrument display, whose 8-inch TFT screen mimics the physical bezel seen in the LFA. The 12.3-inch central infotainment is navigated via touch control whose haptic is much less hyperactive than on previous outings. The screen graphics themselves are a little low-rent, though, and at odds with the striking cinematic sweep of the cockpit.The seats are phenomenally comfortable, as you'd expect, with 28-way adjustment up-front, and similar scope in the rear. Scope also for Shiatsu massage, including spot heaters for the shoulders and lower back. You can forget about air conditioning, too\: the LS 500h has Climate Concierge, which splits the cabin into 16 zones, and monitors the body temperature of occupants.Hmm. Actually driving the damn thing sounds like an intrusion on a masterful, er, experience.Sadly, this is where things become sub-optimal. The LS 500h uses an extended version of the 'Global Architecture - Luxury' platform that underpins the LC 500 coupe. Its chassis is a mix of aluminium and high-tensile steel, and Lexus claims class-leading torsional rigidity. At more than 5.2m long, the new car is no shrinking violet, and 3.1m of that is contained in the wheelbase. But the driver's hip-point is close to the car's centre-of-gravity, which is also lower than before.The position of the engine and hybrid gubbins also promotes better weight distribution, 51/49 front to rear. There's a new multi-link suspension, with double ball joints in the upper and lower control arms for better wheel control, and adaptive damping. Air suspension is standard on the posher versions. An armoury of chassis electronics is gathered under the Vehicle Dynamics Integrated Management (VDIM) umbrella, active rear axle (DRS), and variable ratio steering (VGRS).None of which sounds particularly sub-optimal...No. But the powertrain is. The LS 500h uses a petrol-electric hybrid set-up, the heart of which is a 3.5-litre, normally aspirated V6, backed up by two electric motors/generators fed by a lithium ion battery and harnessed by a continuously variable transmission. The total combined power output is 354bhp at 6600rpm, with 258 torques at 5100rpm. It's worth keeping those numbers front and centre, because a degree of self-flagellation is part of the mix here if it's ethical luxury transport you're after.How so?Come on, does anyone in their right mind really enjoy a CVT? Lexus insists that the new LS 500h circumvents the dreaded 'rubber band' effect, primarily by using what it calls a Multi Stage Hybrid System. So while the CVT is programmed to shift in four stages, the system effectively mimics the linearity and sensation of a conventional transmission across 10 ratios. There's a manual flappy paddle over-ride, and two controllers, sitting like ears on the main binnacle, let you choose between six different drive modes, from Eco up to Sport +. Fairly soon, you realise that this last one will likely see as much use as your least favourite Christmas jumper.Not so much fun to drive, we're guessing.It's off the pace, in more ways than one. There's an ocean of metal to haul along here - 2.2 to 2.4 tonnes depending on spec - and the engine is vocal when pressed. The LS is going into battle with some of the most accomplished wafters in the business, and waft is one thing it struggles to do. What you see in the rev counter and what you feel and hear are somewhat at odds with each other, at least until you settle into a steady state motorway cruise and turn up the sound system. The LS 500h isn't fake news, but it is simulated.The engine needs a turbo, and it could use a lot more refinement. Too many things conspire to ruffle its otherwise precision-engineered sense of calm. What a shame. Crucially, on a very long, mixed run, during which we were categorically not thrashing it. You'd need to drive the LS500h like your entire family were strapped to the bonnet to get the manufacturer's claimed figure.Another quirky, quixotic, frutsrating Lexus, then.I guess so. It's a sensational looking thing on the move, a strikingly contemporary piece of sculpture with elements that verge on the abstract. The cabin is similarly audacious, and we're totally down with the Japanese cultural immersion. But while down-sizing and hybridisation is the new order, this is a car whose best work would almost certainly be done in hock with a different engine altogether. There's much to admire here, but as a package it's currently out of synch.