The Season 4 opener spotlights the 2011 Dodge Challenger. The hour includes a tour of an assembly plant in Canada and a Mexican factory, where its famed Hemi engine is built.

An exotic car built to push performance to the edge while blending Italian elegance is crafted inside Maserati's ultimate factory. It takes 22 days for a Maserati to be assembled and considered road ready and the Maserati GranTurismo Convertible, a $135,000 convertible that tops out at more than 170 mph, is the new pinnacle of performance and comfort.

The hand-built production car, the Dodge Viper, is born, bred and built in Detroit, Michigan. Now NGC takes a unique insider's look at the Viper factory in the current model's last year of production. This ultimate factory is comprised of craftspeople who spend two and a half days building each Viper, which is packed with 600 horsepower that can take it from zero to 60 mph in under four seconds. Without any robots on this assembly line, every Viper is truly hand-crafted.

A Mercedes-Benz factory in Germany is visited for a look at the making of the 571-horsepower 2010 SLS.

It's been 50 years since Rolls Royce created a new Bentley fit for royalty and rock stars, and it's a challenge for Bentley's ultimate factories to construct the Mulsanne, a new design of the luxury car. It takes more than 550 hours and nine weeks for artisans and technicians to create this masterpiece. Precision robots ensure that this two-and-a-half-ton luxury car's body is flawlessly molded, but the finest leather is hand-sewn for Bentley's lavish upholstery.

The Jack Daniel's Distillery in Lynchburg, Tennessee is visited to see how the famous whiskey is made.