These are the photos BMW doesn't want you to see and thanks to the folks at Bimmerpost we have them to share. What exactly we are looking at is still a mystery, but the consensus seems to be that whatever it is, it looks amazing.
There are two strong possibilities for the vehicle, the first being that it's BMW's upcoming Sustainable Sports Car Concept, the second that it is a version of the upcoming 6 Series.
BMW board member Dr Klaus Draeger already said that the company would debut a "green" vehicle, dubbed the Sustainable Sports Car Concept, at the Frankfurt Auto Show in September. This vehicle will be the embodiment of BMW's Efficient Dynamics philosophy, using numerous fuel-saving technologies (like electric power steering, regenerative braking and a stop/start system).
It's also appears to share a resemblance to the M1 Homage that was rumored to be the design inspiration for an upcoming
Bimmerpost forum member (and presumed BMW insider) Scott26, seems to indicate that the car is a concept of the upcoming 6 Series.
Either way, we can't wait to see more of it in Frankfurt.
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