4. Cadillac La Espada
One of the legendary and lost Motorama concepts was the beautiful Cadillac La Espada. Cadillac designed it as an elegant two-seater roadster. The La Espada featured several interesting, innovative features like a power top that created a curved surface when drivers closed it. It also had four headlights.

The car was a perfectly functional prototype with a Cadillac V8 engine delivering 230 HP. As with all other outdated concepts, it was destined for the crusher. However, it looks like it never got there. The story is they sold the car was sold to a private party who stored it in their garage, rarely driving it. After that, they sent it to the scrapyard and it disappeared afterward.