Porsche’s latest video gives us a rare behind-the-scenes look at the development of one of its concept cars, in this case the Panamera Sport Turismo that turned out to be a surprise star of the 2012 Paris Auto Show.  

The video details the concept car’s gestation from initial drawings to the clay modeling stage and eventually its Paris debut, with Porsche design boss Michael Mauer and upcoming design talent Mitja Borkert explaining each of the stages.

Several design insights are revealed, including details of new aerodynamic components being specially developed just for this concept and perhaps future models.

The video also takes us inside Porsche’s R&D center in Weissach, Germany, where virtually all of the automaker’s models are developed.

Porsche hasn’t confirmed whether its Panamera Sport Turismo is headed for production, though it’s certain its design will influence the lines of the next-generation Panamera due out in the second half of this decade.

The concept’s plug-in hybrid drivetrain will arrive much sooner, however, as it is expected to feature in facelifted versions of the current Cayenne and Panamera due in 2014. Porsche will be calling its plug-in hybrid system an e-hybrid, which is an advanced development of the parallel full hybrid the automaker already implements today in the Cayenne S Hybrid and Panamera S Hybrid models.

The e-hybrid’s electric motor currently produces about 95 horsepower, and is matched to a supercharged 3.0-liter V-6 engine producing 333 horsepower on its own. Working together, the two power sources can accelerate a vehicle the size of the Panamera from 0-60 mph in around 6.0 seconds or less.

Using a mix of electric and gas driving, Porsche’s e-hybrid system could return a fuel economy as high as 67 mpg. The electric-only driving range is about 18 miles in the Panamera Sport Turismo.