The strong possibility exists, dear TopGear.com reader, you're not exactly bursting to know what the next Lexus LS would look like. After all, the LS has always been a big sedan that's understated to the point of being entirely mute. But this is about to change.

At the Tokyo Motor Show Lexus wheeled out the LF-FC concept. It's lower, sleeker, and frankly has more of a raunch about its haunches than any Lexus sedan before.

It 'expresses our progressive luxury and high-tech vision of a not-so-distant future,' says Tokuo Fukuichi, Lexus International President.

The cabin is gorgeous, and features a new interface with gesture control. That's the spooky hologram softball thing on the centre tunnel. And the LF-FC can also gesture to other traffic, projecting messages onto the tarmac to warn cars or pedestrians it's coming, or wave them on. How very well brought-up.

They won't hear it coming though, because it runs silently on a fuel cell. Hence the name. All Lexus concepts are called LF (Lexus future) and FC is fuel cell. Lexus, like Toyota already does, has said it will have a fuel cell inside five years. Could the new LS be that car?

Well, the concept has very interesting packaging. The whole fuel-cell stack and electronics have been put under the bonnet where the current LS (and almost any other car) has its engine. There's one hydrogen tank between the front seats, in place of the gearbox, propshaft and exhaust. Another tank is transverse, ahead of the rear suspension, in the petrol tank's usual home. Finally the hybrid battery sits where a LS600h already has its battery.

In other words, the next LS could easily be sold in both petrol-hybrid and fuel cell versions.

Like any new luxo-sedan, it's prepared for highly autonomous driving. But the claim runs that it's also good to drive, thanks to good weight distribution and the drive system. The rear wheels are driven by a powerful but compact motor mounted between them, and each front corner gets its own small in-wheel motor, for 4WD and torque vectoring.

Back to Fukuichi: 'We're preparing a new chapter for Lexus. This car is a pointer to the direction we will be travelling.'