A new exhibition at the Porsche Museum in Stuttgart aims to showcase the stillborn models that never made it into production.

‘Project : Top Secret’ opened on Wednesday, September 17, and will run until Sunday, January 11, giving visitors an insight into five decades’ worth of Porsches that never saw the light of day.

Of particular interest is the four-door 989; a front-engined, V8-powered four-door sports saloon that was cancelled because of rising development costs.