Playing the game of “what might have been” can be either a pleasant or melancholy exercise. Oftentimes this speculative practice can be a stimulating intellectual diversion. What would have happened if the pre-Columbian Chinese expeditions to the New World had established a beachhead? What if Napoleon had not tried to invade Russia? Such historical speculations concerning forgotten turning points provide cerebral thrills and wistful musings on children unborn, deeds undone, cities unbuilt.

But what of the art that went unfinished or unnoticed? That’s the central concern of “Lost Transmissions: The Secret History of Science Fiction and Fantasy,” a collection of essays by various hands, with half the text contributed by editor Desirina Boskovich and a graceful foreword by Jeff VanderMeer. “This book conjures up not just a sense of wonder,” VanderMeer writes, “but also gives readers the sweet regrets of might-have-beens.” Additionally, the compilation is lavishly illustrated and arrayed by master designer Jacob Covey.

“Lost Transmissions” focuses on all things fantastical, broadening its remit to include literature, film, television, architecture, art, design, music, fashion and fandom. But it’s not solely concerned with a catalogue of phantoms. As Boskovich says in her introduction, the book will consider “the work of artists who, for whatever reason, did not receive their due.” Meritorious cult figures, in other words, unappreciated and overlooked.

This variant of the might-have-been game does not focus precisely on seminal things that never happened, but on worthwhile things that did happen but engendered less-than-optimal consequences. In fact, the majority of the entries are along these lines and ultimately overpower the instances that look at formally unreified works. But in the end, the parallel themes prove satisfyingly complementary.

The intelligently curated selection of topics mixes some pretty well-known icons — artist Jack Kirby, writer Angela Carter, musician David Bowie — with some out-of-left-field wonders: manga creator Tsutomu Nihei, Afro­futurist writer Henry Dumas, TV show “Space Island One.” Any reader’s ratio of familiar to unknown topics will vary, of course. But as someone who’s been immersed in fantastika for five decades, I’d have to say that Boskovich scores pretty high on the worthily esoteric scale. There’s plenty here to intrigue and enlighten even the most jaded reader/viewer/listener/game-player.

Each essay is meant to summarize the virtues and history of its subject and also place it in good historical context. On another level, the table of contents is meant to limn a kind of counter-canon, an alternate history of fantastika where, say, “Star Wars” is the minor hobbyist project of the guy who created “THX 1138” and the transgressive novels of Kathy Acker (extolled with zest by Nick Mamatas) outsell those of J.R.R. Tolkien. Some of the essays do a better job of projecting the canonical potentials than others, but all succeed admirably in conveying what makes each topic worthy of our attention. All the contributors exhibit enthusiasm, knowledge and concision. The bite-size chapters make this a book that’s easy to dip into whenever the reader has a spare moment.

Boskovich sets the tone with a conversational style that enwraps solid scholarship. The other contributors follow suit, with lively essayists such as Grady Hendrix (“It’s a Man’s, Man’s, Man’s Apocalypse”), Annalee Newitz (“X-Ray Spex, Poly Styrene, and Punk Rock Science Fiction”) and Ekaterina Sedia (“The Fashion Futurism of Elizabeth Hawes and Rudi Gernreich”) bringing humor and erudition to bear.

Among the items that deal with unborn wonders, we learn about gems such as the Who’s Lifehouse album (“a science-fiction rock opera that would expand the potential of audience participation to dizzying new heights”), C.S. Lewis’s fragment of “The Dark Tower,” Harlan Ellison’s infamous anthology “The Last Dangerous Visions” and Weezer’s “Songs From the Black Hole.”

Ultimately, this book recalls the darker, pioneering, more transgressive work done by RE/Search Publications in landmarks such as “Incredibly Strange Films,” “Modern Primitives,” “Angry Women” and others. And while “Lost Transmissions” would like to sketch out a cultural counternarrative as complex and rich as Greil Marcus’s “Lipstick Traces,” it never quite attains that meteoric escape velocity. Nevertheless, the collection will broaden your horizons and turn you on to wonders bubbling under the mass-market commodified pleasures to which we all too often limit ourselves.

Paul Di Filippo’s most recent novel is “The Deadly Kiss-Off.”

LOST TRANSMISSIONS

The Secret History of Science Fiction and Fantasy

Written and edited by Desirina Boskovich

Abrams. 304 pp. $29.99