Prior to Audi taking control of Lamborghini in 1998, a last-minute agreement was signed in Sant'Agata between the Italian supercar maker and French coachbuilder Carrosserie Heuliez to create a one-off model in order for Hueliez to celebrate its 50th participation at the Paris Motor Show. Based on a Diablo, the result was the radical-looking Pregunta (Spanish for "question") that was presented first at the 1998 Paris Auto Show and then at the 1999 Geneva Motor Show.

Upon taking the reins at Lamborghini, Audi demanded the cessation of all existing prototype products, which makes the Pregunta the last bespoke coachwork ever built on an original Lamborghini base. Hand-built in Heuliez' Turin studio in Italy, the one-off Lamborghini Pregunta Speedster concept boasted a 530 horsepower V12, and was capable of hitting a 207 mph top speed. Inspired by the space and aircraft industry as well as Formula 1 racers, the Diablo's all-wheel-drive set-up was replaced with a lighter, more extreme rear-wheel drive structure with radiators moving to the front.

Two "half-roofs" in transparent polycarbonate transform the ultra-low speedster into a closed berlinetta, while unique features consist of a Dassault stealth paintwork, fully electronic F1-style Marelli instruments, rearward facing cameras replacing the mirrors, optical fiber lighting and a combat-jet derived cockpit setup. Other design highlights on the Pregunta include the giant saurian backbone atop the massive engine lid, racing prototype-style nose, enormous front spoiler, and reactor-like lateral air scoops. To own the last Lamborghini before the brand was swallowed up by the VW Group, interested parties wll have to stump up 1.6 million Euros.