Modern science fiction came of age in the 1950s, and it was in America that the genre broke most exuberantly free from convention. Moving beyond the pulp magazines, science fiction writers stretched their imaginations at novel length, ushering in an era of stylistic experiment and freewheeling speculation that responded in wildly inventive ways to the challenges and perplexities of an era of global threat and rapid technological change. Long unnoticed or dismissed by the literary establishment, these “outsider” novels are now recognized as American classics.

This, the first of two volumes surveying the decade’s peaks, presents four very different visions of uncertain futures and malleable selves. Frederik Pohl and C. M. Kornbluth’s The Space Merchants (1953), acclaimed in its day by Kingsley Amis as “the best science fiction novel so far,” brought a ferocious, satiric edge to its depiction of a future world dominated by multinational advertising agencies. In Theodore Sturgeon’s More Than Human (1953), a group of damaged individuals finds a strange new fulfillment in what may be the next stage of evolution.

Leigh Brackett was one of the first women to make her mark as a science fiction novelist. In The Long Tomorrow (1955), she pits anti-urban technophobes against the remnants of a civilization that destroyed itself through nuclear war. The hero of Richard Matheson’s fable-like The Shrinking Man (1956), condemned to grow ever smaller by a mysterious cloud, moves through humiliations and perils toward what Peter Straub calls “a real surprise . . . a fresh, wide-eyed step into a world both beautiful and new.”

Here are four classic novels that, each in a different way, open fresh territory, broaching untried possibilities and brimming with the energies of an age fearfully conscious of standing on the brink of the unknown