This car is called a 1958 Cadillac Eldorado Biarritz, but very little of it is shared with the Biarritz that you could have purchased from a dealer that year. The body, from the doors back, is paneled in hand-laminated fiberglass, including the 1959 prototype fins, which are identical to those used on the production cars, save for the small “bullet” lights that screw on from the outside and the molded chrome spears on the front fenders and doors. All of the body moldings were eliminated, save for the wheel opening moldings; the lower part of both the front and rear bumpers were color-matched to the car; and the backup lights were relocated under the license plate frame.

Numerous codes and numbers appear throughout, with a metal tag bearing original styling project codes and numbers on the back of the rear seat, and many of the unique trim pieces have the designation SO 90175, 90175, or #5 on them throughout. In addition, many of the hard trim pieces have drawing numbers stamped, molded, or etched on them, which confirms the car’s original custom-built authenticity.

The interior is just as special, with four bucket seats arranged around a console that contains an ice bucket and a humidity sensor. That sensor is part of the most special feature of this car, the “Raindrop,” which is one of General Motors’ most fascinating gadgets of the 1950s. The Raindrop never actually made it out of the prototype stage, but it is believed to have been installed for testing on three 1958 Eldorado Biarritz, of which this car is one.

On this particular car, the Raindrop system utilizes three major components, the convertible top itself, a three-piece metal top boot, and a humidity sensor mounted between the front bucket seats. When a few drops of water strike the humidity sensor, the main center section of the top boot moves rearward into the trunk area, while the two pieces alongside fold down into the rear quarter panels. The top then rises automatically and lowers onto the windshield’s header bar, where it automatically screws down. The power-vent windows close, followed by the windows in the doors and then the rear quarter windows. Voila! A top that has closed on its own, with no human intervention required.

The car was reportedly given to former GM Styling Director Harley Earl for his Florida retirement, and there is a 1991 letter on file from Richard H. Stout, of Delray Beach, which attests to his having seen Earl in the automobile and that the car was equipped with a Raindrop system at that time. Later, it was purchased by a Cadillac dealership in Dayton, which began a restoration that utilized a new 1958 Coupe deVille frame, engine, and drivetrain, along with the original car’s bodywork and special features. The restoration was completed by the next owner, with the car appearing as the cover feature of the March 1998 issue of Cars & Parts magazine. It was eventually sold to prominent Florida collector Al Wiseman before passing into the ownership of the Andrews Collection, where it has remained a well-maintained visitor-favorite for a decade.

As one of only two Raindrop cars that survive, and the only example with a functional top system and special design features, this is arguably one of the most important and historic of all post-war Cadillacs.