One of the most exciting launches at this month's Frankfurt Auto Show will be BMW's new plug-in hybrid sports car, the i8.

The German automaker has released a teaser video of the new car ahead of its official debut on September 10, where it'll join the existing i3 electric city car on BMW's stand--and pave the way for future BMW electric vehicles.

Both i3 and i8 debuted in concept form at the last Frankfurt Auto Show in 2011, and each car's design has changed remarkably little. While some of the more unusual touches have made way for production reality--the low glass doors have been replaced by more conventional units on each vehicle--the overall shape of the i3 and i8 has remained much the same.

That's even better news for the i8 than it was the love-it-hate-it i3. While the most recent official shots are still lightly clothed in camouflage, the i8's low-slung sports car styling is easy to make out, as are more striking details such as the wing-like rear lights and the low, shark-nosed front end--not dissimilar to its much-vaunted spiritual predecessor, the M1 supercar of the 1970s.

The M1 used a familiar BMW inline-six cylinder engine, but BMW's latest high-performance sports car halves that, with a 1.5-liter, 3-cylinder turbocharged unit. With an electric motor to help out, total system output is 362 horsepower. With 420 lb-ft of torque on offer, BMW quotes a 0-60 mph sprint time of "under 4.5 seconds" and a top speed of 155 mph.

Other pertinent numbers are the car's total range of "over 310 miles", its 22-mile electric range, and 95 mpg combined economy--all of which are recorded in European testing, and will therefore differ by the time the car hits the U.S. market in 2014.

For more technical details on the i8, head over to our most recent guide--and you can read up on more Frankfurt launches on our official show page.


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