Seen this yet? It's the Ford Iosis. A sort of Mondeo-sized four-door coupe. Think Mercedes CLS, but scaled down a bit.

Trouble is, you can't buy it. Not in this form anyway. But this car matters because it shows the kind of talents who are operating at Ford design these days, and the kind of freedom they are being given.

It shows some ideas that will take shape (literally) in the 2006 Mondeo, and more so in Fiestas and Focuses beyond.

The Iosis, though, is just a show car - a bit of stand-candy at the Frankfurt motor show from mid-September.

Press the unlock button and it's obvious this is just one-off. Presto, the doors themselves pivot upwards on an insanely expensive and complicated system of powered arms, like something arachnid. It's beautiful and scary at the same time.

That door opening is important because it properly reveals the extraordinary interior. Again, strictly a one-off. Can you imagine affording a real car where each facia vent was composed of 11 separate hand-made metal parts? But it's hinting that Ford cabins will become more driver-focused in future.

In fact that's really the whole point here. Fords are already exciting to drive. Better than many of the admired 'premium' brands. Even as it hobbles into its last year of life, the Mondeo is more fun than a brand-new equivalent Audi A4. So from now on Ford wants to do visual excitement like it does down-the-road excitement.

So what relationship does the Iosis have with the next Mondeo? You don't have to be a rocket scientist to deduce that the real Mondeo will have normal doors, smaller wheels and a black plastic dashboard.

It will have to have bigger windows at the back. The boot will have a lid that lets flat-pack wardrobes in. The roof will be higher.

So, says Martin Smith, Ford's European design chief, Iosis 'has elements of future Ford cars. But it's such a free interpretation of those elements that it couldn't possibly be the next Mondeo.

They are related though. If the Mondeo will be the older brother in the Boss suit, this is the younger brother, a super-fit boxer down the East End in a tracksuit.'

Iosis does tell us the design elements Ford will use. They're just exaggerated for effect here, so that they can get noticed over the babel of visual hubbub that is an international motor show.

Iosis elements that will be carried forward in mildly toned-down form include:

Trapezoid lower grille

Headlamp shape

Bonnet flaring back from the upper grille

Dishing at the base of the windscreen

Big wheel-arches and the muscular contours above them

Strong shoulders, and cut-in flanks below

High prominent tail lamps echoing the headlamp shape

Five-sided rear window.

You can see more pictures of the Iosis in the October issue of Top Gear magazine - on sale now.

And you can also read about the amazing process of hand-building it from scratch. Show cars are commonly valued at £1 million plus. Well, I went to Turin to watch a team of magically gifted craftsmen bash, weld, grind and finesse it out of slugs of raw material. And I came away thinking that figure is a bargain.

Paul Horrell
Consultant Editor, Top Gear magazine