The star of the North American International Auto Show sat on the main floor at McCormick Place in Chicago, less than a month after her show-stopping debut in Detroit.

Barely noticed.

The Cadillac CTS Coupe Concept was so stunningly beautiful when driven onto the show stage at Detroit that even those journalists who talk incessantly during these reveals were momentarily stunned into low murmurs.

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But, in Chicago, not even a hundred feet away from the GM show stage, the CTS Concept Coupe sat, slowly revolving on a turntable and ignored by everyone.

Perhaps fame really is fleeting. It could be, too, that media types – the ones attending these press preview days – really are nothing but headline hunters, a lemmings slavishly following whatever story of the day is served up to them by the car makers. But, not even the local television reporters bothered to pause to pose in front of the CTS Coupe.

Of course, the story of concept cars is usually a sad one. Often they don’t survive much beyond those moments of glory. Were the very first ever Corvette – the car exhibited by General Motors at the Motorama held at New York’s Waldorf-Astoria hotel still around, it would be worth millions. It is, sort of, still around. But, not as it was exhibited. Over the years, Chevrolet used it as a mule, a test bed for development. It was ultimately used to test the V-8 introduced for the 1957 model year.

At least it survived. A number of them didn’t. Some met almost glamorous ends. One of the Ghia-built Chrysler concept cars of the 1950’s was aboard the Italian Lines luxury liner Andrea Doria when she sank off New York in 1956. But many of the General Motors dream cars were cut up or crushed. Indeed, a junk yard, oddly named Warhoops (the proprietor’s name, as it turns out) but conveniently located to the General Motors technical center in Warren, Michigan, became the designated graveyard for a number of the 1950’s Motorama dream cars, including the Cadillac Brougham and the Chevrolet Biscayne of the mid-50’s. The story is that the cars were sent there to be destroyed and a GM executive accompanied them to insure that the job was accomplished. But, he was anxious to go home and the Warhoops guys were anxious to do other things, so they cut the cars into quarters and the executive signed off. Forty years later, the cars were discovered and the Brougham has been restored, the Biscayne is in the process.

Then, there’s the Lincoln Premiere show car from about 1956. Once it had done its duty on the show circuit, it was sold. The original king of California customizers, George Barris, was hired by a movie studio to transform it. When he was done, the car had become the first Batmobile.

Some concept cars do, course, survive. Barrett-Jackson’s auction house lately has made a killing selling concept cars to Microsoft founders and others with large sums of unused money. For the last three decades, a collector named Joe Bortz has created a trove of collector cars from all of the manufacturers. Some have been retained by the manufacturers. When the Daytona 500 ends on February 17th, the winner will be handed the Harley Earl trophy. On top of the trophy is a replica of the Firebird II, a GM concept car styled like a jet and actually powered by a turbine. The real car is still in the GM Heritage Collection, where GM also still holds the very first concept car – the “Y Job” designed by Harley Earl in the 1930’s.

Of course, the ultimate future for the Cadillac CTS Coupe Concept is quite bright. It is reasonable to expect that when these same media types assemble next year in Detroit, they will be there to see the production version of the CTS Coupe drive onto the show stage. No doubt, the talk then will be about how long we must wait for the CTSv version. The GM executive types will be teasing their journalistic audience with advanced rumors of the convertible version of the CTS.

By then, one hopes, the CTS Coupe Concept will have been honorably and gracefully retired to a spot in the Heritage Collection, an honored spot in the genetic evolution of Cadillac.

In the CTS Coupe Concept, whether or not it realizes it, Cadillac has achieved its future.

In popular conception, the heritage of Cadillac is tail fins.

But, the essence of Cadillac was always defined by one William Mitchell. At age 28, he was the head of the Cadillac design studio. It was he who designed the original Cadillac Sixty Special of 1938, a car that was to ultimately define the entire line, in both appearance and purpose. It was Mitchell who took Cadillac away from tail fins, who created the original 1967 Eldorado, who gave Cadillac the English grace that became the first Seville, and who defined the concept of Cadillac’s restrained but obvious elegance in the late 1960’s.

The essence of Cadillac has always been a clean, quiet, and obvious elegance, a purity and simplicity of line so perfectly executed that it was actually ostentatious in it ultimate executing.

Think the 1997 Seville STS. The 1966 Cadillac Eldorado convertible. The 1967 Eldorado, the first on the separate chassis.

Think, even, the current CTS.

The CTS Concept Coupe, however, is special.

It shows that there is a soul in the company that produced it, one that is not always overpowered by the commercial practicalities that produce such as the Traverse, an exquisitely executed Frigidaire of a car.

During the Chicago Auto Show, we were treated to many future scenarios, some visionary.

But, one hopes, somewhere at General Motors, someone understands that the CTS Coupe Concept is the DNA of the company.