"Glass Bead Game" is a literal translation of the German title. The title has also been rendered as Magister Ludi. "Magister Ludi", Latin for "master of the game," is the name of an honorific title awarded to the book's central character. "Magister Ludi" can also be seen as a pun: lud- is a Latin stem meaning both "game" and "school."
The novel follows the life of a distinguished member of the order, Joseph Knecht (the surname translates as "servant" or "farm hand" but can also mean "vassal" or "knight"), as narrated by a fictional historian of the order. Hence the novel is an example of a Bildungsroman. The text, written in a scholarly biographical style, chronicles the precocious protagonist's decision to join the order, his mastery of the Game, and his advancing in the order's hierarchy, eventually being given the title Magister Ludi, reserved for the Game's finest player.
However, Knecht's loyalty to the order is brought into question as he gradually comes to doubt whether the intellectually gifted have a right to withdraw from life's big problems. Knecht comes to see Castalia as a kind of ivory tower, an ethereal protected community, devoted to pure intellectual pursuits, but oblivious to the problems posed by life outside its borders. This conclusion precipitates a personal crisis, and accordingly, Knecht does the unthinkable: he resigns as Magister Ludi and asks to leave the order, ostensibly to become of value and service, in some way, to the larger culture. The heads of the order deny his request to leave, but Knecht departs Castalia anyway, initially taking a job as a tutor to his childhood friend's son. Only a few days later, he drowns in a mountain lake while attempting a swim for which he was not fit. The story ends abruptly.
The narrator breaks off before the final sections of the book, remarking that the end of the story is beyond the scope of his biography. The concluding chapter, entitled "The Legend", is reportedly from a different biography. After this final chapter, several of Knecht's "posthumous" works are then presented. The first section contains Knecht's poetry from various periods of his life. Then three short stories follow. The first tells of an ancient pagan named Knecht; the second of Josephus, an early Christian hermit; and the final story covers the life of Dasa, an Indian prince who grows up as a cowherd. All three stories cover the lives of spiritual seekers who learn the mystic traditions of their respective eras from sagacious teachers. Originally, Hesse intended several different lives of the same person as he is reincarnated. Instead, he focused on the story set in the future and placed the three shorter stories, "authored" by Knecht, at the end of the novel.