When they first appeared in 1978, the 3 ??-inch Star Wars figures transformed the action-figure industry. Before the Star Wars figures, American boys played with 12-inch G. I. Joe figures and their 8-inch to 12-inch imitators. (Hasbro itself was forced to reduce the size of its G. I. Joes in the 1970s because a worldwide oil embargo made scarce a key ingredient in the manufacture of plastic action figures.) The smaller Star Wars figures used less plastic, cut costs, and fit better in the hands of the kids who collected them. For decades after the arrival of the smaller action figures, toy makers issued their own imitations of Star Wars figures (even G. I. Joe), each with a line of accessories, play sets, and vehicles, supported by an intricate back story of good versus evil, and explained in detail in supporting movies, TV shows, comic books, and other media.