THERE'S BEEN A LOT of squabbling online lately about what exactly defines a "geek." When 90 percent of summer blockbusters are based on comic books and beautiful actresses regularly out themselves as nerds on late-night TV, something has clearly shifted in terms of how once-scorned pursuits are now perceived. And, of course, some lifelong geeks are up in arms that "their" culture has been appropriated.

If you find yourself identifying with the preceding paragraph, go find yourself a copy of Ernest Cline's Ready Player One IMMEDIATELY, because you've clearly forgotten how to have fun. This book will remind you: Cline's first novel is an unabashed celebration of geek culture that ingeniously marries sci-fi, young adult, and pure, uncut nostalgia.

In 2044, an oil crisis has devastated the US economy and most people spend their time immersed in an online artificial reality called OASIS. When the wealthy designer of OASIS dies, he leaves his fortune hidden inside the game, with only a few cryptic lines of verse hinting at its location. The only other lead: The man's well-known obsession with the movies, science fiction, videogames, and pop culture of his youth.

Eighteen-year-old Wade Watts is one of thousands who devote themselves to the study of the geek culture of the late 20th century in hopes of finding the key to the hidden fortune. From Pac-Man and Dungeons and Dragons to Spaced, Firefly, and Monty Python—if it's geeky, it might be a clue. As Wade and his friends struggle to solve the puzzle, they're racing against a dangerous corporation that's determined to win the fortune—and ultimate control of OASIS—for itself.

It's old hat to imagine a future in which all life is lived online, but Cline freshens up this familiar trope by presenting a virtual reality that is in some ways superior to reality itself. (Education is free and sophisticated online, for example.) He's sensitive, too, to the myriad personal and political reasons his characters might prefer to spend their days inhabiting anonymous avatars rather than their own bodies. (One of the book's sweetest subplots is about Wade and his friends nervously meeting in real life for the first time.) Player One isn't a perfect book—the nerd references can be closing, and the story's momentum hits a few roadblocks. What its is, though, whether you're into classic arcade games or John Hughes movies, is fun. Just like geeking out should be.