The novella is ostensibly concerned with a chess match conducted on a cruise liner between opponents of contrasting character type and the epic struggle between the two adversaries.
Mirko Czentovic is a peasant prodigy possessing no obvious redeeming qualities who has exploded onto the world chess scene. Despite his inability to play from memory (blindfold chess), which Zweig likens to a concert pianist's inability to perform without a written score, he bludgeons his way to a world title in a quest for fame and monetary reward.
In contrast, his opponent in the final match, Dr B, possesses immense imaginative capacity for the game and indeed has only managed to survive solitary confinement by the Nazis due to his extraordinary ability to play chess entirely in his mind.
The story's main theme is the exploration of the relationship between chess and madness.
Driven to mental anguish as the result of his incarceration, Dr B maintains his sanity through his discovery of a book of master games which he plays endlessly, voraciously learning each one until they overwhelm his imagination to such an extent that he becomes consumed by chess. Zweig calls the result of this obsessive behaviour chess poisoning. After absorbing every play in the book, Dr. B begins to play the game against himself, developing the ability to separate his psyche into two personas: loser and winner. This conflict causes him to ultimately suffer a breakdown, after which he eventually awakens in a sanatorium. His greatest power is also his greatest weakness: he reenacts the match in his mind repeatedly with all imaginable possibilities so rapidly that Czentovic's deliberation and placidness drive him to distraction and ultimately insanity, culminating in his dramatic defeat.
The story mirrors the events of a war-torn world in which Zweig observed a brutal, boorish peasant's risen to dicatorial power in Germany. Czentovic is, in this way, a representation of Adolf Hitler while his opponents, aside from Dr. B, symbolize the fractured allies.