The upcoming BMW M8 has been spied inside and out this week at the famed Nurburgring circuit in Germany.

Set to become the company's flagship when it debuts sometime next year, the M8 has already been previewed by its GTE race car counterpart in preparation for the 2018 FIA World Endurance Championship (WEC) season next year.

There's still a heavy amount of camouflage on the prototype in these images, though we can expect the production version to look something of a mix between the M8 GTE racer and the Concept 8 Series show car revealed earlier this year.

At the front are large intakes, likely feeding air to the turbocharged engine, while quad tailpipes at the rear are a hallmark of BMW M cars.

What's news this time, however, is that our photographers managed to snap images of the prototype's interior - though the black sheets and camouflage don't really lend much to the imagination.

Viewable is the steering wheel, which appears to be lifted straight out of a 5 Series or 7 Series – expect a sportier BMW M rim for the production model – along with the regular rotary dial and array of buttons used to control the iDrive infotainment system.

However, the buttons visible next to the gear wand appear to be more plentiful than normal with a different layout, hinting at some changes that should debut with the new flagship 8 Series range.

Meanwhile, the boot looks to be of a decent size, though in these pictures it's filled with equipment and a rolled up sheet.

BMW hasn't detailed what will power the road-going version of the M8, however, the M8 GTE racer features a 4.0-litre twin-turbo V8 with "more than 500hp (368kW) depending on the classification" - hinting that a version of the M5's 441kW/750Nm bi-turbo V8  is likely to reside under the bonnet.

Stay tuned to CarAdvice for more BMW M8 updates in the coming months.

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