Sometimes mistaken for an early Dodge Charger, the fastback AMC Rambler Marlin hit the street in 1965, a year before the Dodge. Based on the Rambler Classic, most Marlins had 270-horse 327 V8s and all had seats that folded down to form a bed (a feature that must have come in handy on a hot drive-in date to a Russ Meyer triple-feature). Sadly, the Marlin faced stiff competition from Detroit iron with bigger engines and fatter marketing budgets and failed to sell well; in 1967, the Marlin nameplate was shifted to a fastback version of the Ambassador, in an unsuccessful attempt to compete with fastback Galaxies and Impalas. The real disappointment: Renault didn't make a version of the Marlin in South America.
The Story of the AMC Marlin Automobile [Concord University]
Related:
Rambler Rogue? No, Renault Torino! [internal]