BMW releases present day photos of it's best kept secret, the M8. It was rumored to be destroyed, but it was under lock and key. The M8 is a prototype that never went into production---unless you count rebadgers. The M8 is M division's take on the 8 series, they had a quasi-product in the 850CSi, but it was not a full bore M Division effort. The M8 was, it had a 550 hp version of the S70 V12 (the version in the Mclaren F1 is the S70/2). You may also note, that this prototype had no headlights.
Do to the Recession of the early 90s, this car was never produced.
This car, along with the M Division's X5 LM, rank as one of the company's most extremely guarded cars
http://www.bmwblog.com/2010/07/02/exclusive-photos-bmw-m8/