The Cadillac Sixty Special marked a new direction at Cadillac, and for American automobile styling, too.

The  dramatic rendering above—a proposal for the car that bcame the 1938 Cadillac Sixty Special–is the work of William L. Mitchell. A design prodigy, he was 23 when General Motors styling boss Harley Earl appointed him to head the Cadillac studio in 1936. Twenty-odd years later, he would replace Earl as vice president of styling, becoming  the second person in GM history to hold the position. It’s said Mitchell drew his free-wheeling inspiration for the Sixty Special from a multitude of sources, including the Miller front-drive Indy cars.

The car that made the SIxty Special possible was Cadillac’s 60 Series introduced in 1936 (above). Considerably smaller than the rest of the Cadillac line, it was a product for a changing economy and changing times. More than 1,000 lbs lighter than the biggest Cadillacs, the 60 Series was based on the recognition that now, luxury cars were usually driven by their owners rather than chauffeurs. While its styling was strictly conventional, with a three-inch stretch in the wheelbase the 60 Series made an ideal platform for Mitchell’s transformation.

As a young car enthusiast himself with the natural preference for smaller cars, Mitchell gave the Sixty Special the look of a sporty convertible sedan, with bright trim around the windows but with a fixed steel top. The roof pillars were slimmed down and there were no running boards.There was a single body style, a four-door sedan, but with an extended tail and trunk—like a coupe. Styling historians regard the Sixty Special as the Motor City’s first three-box sedan. They also hold that here was the first car design developed with a distinct “upper” and “lower” north and south of the beltline.

Mitchell’s Sixty Special was the best-selling Cadillac model for 1938, launching one of the most remarkable careers in automotive design. The price was $2,090, around $800 more than a standard 60 Series but less than half the cost of a big 65 or 75 Series, and buyers rushed in, The coachbuilt era was ending, and the Sixty Special demonstrated that the most advanced styling need not be confined to the most expensive models. In one form or another and with a few breaks, the Sixty Special name would reside in the Cadillac lineup through 1983.