The secret's out: just days after Rolls Royce announced it would be testing its new car platform on the road, our snappers have caught the next-generation Phantom saloon being put through its paces in disguise.
The super-luxury saloon isn't expected to arrive until 2018, which is the same year that we'll see the brand's first SUV (dubbed the Cullinan). Yet even though this is a very early production mule, it's clear to see the evolution of the Phantom's classic shape.
It's unmistakably Rolls at the front, with the bluff nose, iconic grille design and LED headlamps. The bonnet is vast, appearing even longer than the current car, while the windscreen is a bit more steeply raked.
Side-on, it looks taller than you might expect, while the rear-hinged back doors remain. Look closely at the roof and you'll see the shark-fin antenna from the BMW 7 Series, while the rear window shape and bootlid profile is more sloping than ever.
The current Phantom has been on sale since 2003, with the Bentley Mulsanne rival receiving only a facelift and tech update in 2012. The long overdue replacement will bring with it advanced safety and entertainment tech from the latest 7 Series, but should retain the peerless Rolls interior quality.
The MEB modular platform under the skin is an aluminium space-frame architecture, set to be shortened from this LWB Phantom for use in the SUV. BMW's expertise will likely bring carbon-fibre reinforced plastic (CFRP) to help keep weight down further.
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We still expect the Phantom to retain a traditional V12 engine layout, but there's not indication yet whether Rolls will follow the industry trend and introduce turbocharging. Engineers have previously hinted a plug-in hybrid powertrain will be offered, too.