In its heyday during the 1950s, Motorama delivered G.M.'s message of postwar optimism to millions of curious spectators. The 1938 Buick Y-Job was the first such dream car.

The 1951 LeSabre, with its tail fins and lightweight components, shows the influence of jet plane styling.

The 1956 Buick Centurion was the first car designed by Chuck Jordan, who would later become G.M.'s styling chief.

The Cadillac Cyclone was first shown in 1959.

In 1950, G.M. borrowed the name of its permanent Chicago Museum of Science and Industry exhibit to rechristen its New York fashion show the Midcentury Motorama.

Unfettered by concerns over the cars’ production feasibility, designers toyed with extravagant shapes, exotic propulsion systems and impractical gimmicks. Seen here is the Futurliner from 1953.