Haroun is a kind and curious boy whose life is disrupted when his mother abandons the family. The trauma of her departure at eleven o'clock shatters his concentration, leaving him unable to focus on anything for longer than eleven minutes. Driven by a deep sense of loyalty, he travels to the magical moon of Kahani to restore his father's lost gift of storytelling.

Rashid is a famous storyteller known affectionately by his fans as the Ocean of Notions and mockingly by his detractors as the Shah of Blah. He relies on a magical subscription to the Sea of Stories to fuel his political speeches and public performances. His entire livelihood and identity collapse into despair when his wife leaves him, draining his imagination and silencing his voice.

Iff the Water Genie is a bureaucratic employee from the magical moon of Kahani. He carries a wrench-like tool called the Disconnector, which he uses to turn off the story supply for earthlings who lose their subscriptions. He reluctantly becomes Haroun's primary guide, introducing the boy to the fantastical creatures and rules of the story realms.

Khattam-Shud is the evil ruler of Chup and the Cultmaster of the idol Bezaban. His name literally translates to "The End," reflecting his desire to eradicate free speech and imagination, which he views as unrulable threats to his power. He orchestrates a massive plot to poison the Sea of Stories and plug its source entirely.

Blabbermouth is a highly skilled Page in the Guppee military. Because the army does not allow girls to serve as Pages, she disguises her true identity, hiding her long hair under a cap to pursue her dream career. She is a talented juggler who equates the physical balancing of objects to the verbal balancing of a good tale.

Soraya is Haroun's mother and Rashid's wife. She grows increasingly frustrated with her husband's constant daydreaming and immersion in make-believe, believing he is too unserious for real life. She ultimately leaves her family for a practical neighbor, plunging Rashid into a creative crisis.

Mr. Sengupta is the Khalifa family's upstairs neighbor in the sad city. A stern and intensely serious man, he completely lacks an imagination and views fiction as a useless distraction from real life. He successfully lures Soraya away from her husband, serving as an earthly parallel to the novel's primary villain.

Butt the Hoopoe is a large, mechanical bird that serves as primary transportation across the magical moon of Kahani. He communicates telepathically and possesses the exact voice and conversational quirks of an earthly mail coach driver. He strongly believes in the ethical necessity of exercising free speech.

Mr. Butt is the energetic driver of the mail coach assigned to take Rashid and Haroun into the Valley of K. He is a large man with wild hair that resembles feathers. He is eager to please his passengers, even if it means driving at terrifyingly dangerous speeds along winding mountain roads.

The Walrus is the bald, mustachioed comptroller of P2C2E (A Process Too Complicated To Explain). Operating out of Gup City, he is a high-ranking authority figure who manages the intricate, unexplainable systems of Kahani, including the granting of wishes and the synthesizing of story endings.

Prince Bolo is the dramatic and often foolish royal leader of Gup. He is fiercely devoted to his kidnapped betrothed and focuses entirely on rescuing her from the dark lands of Chup. His single-minded romantic devotion frequently overrides his tactical sense, leading him to ignore practical advice.

Princess Batcheat is the royal princess of the bright land of Gup. She has been kidnapped by the enemy forces of Chup and imprisoned in an ice castle, where she is scheduled to be sacrificed at a dark festival. Her plight initiates the formal war between the two realms.

Mudra is the Champion Warrior of Chup and a former trusted lieutenant to the evil Cultmaster. Having grown disgusted with the oppressive Silence Laws, he breaks away from his dark master. He communicates through an intricate, rapid sign language that Rashid can translate.

General Kitab, also known as the Speaker, is the military leader of the Guppee forces. Unlike traditional generals, he actively encourages his soldiers to argue, debate, and chatter constantly, believing that an army bound by free speech is stronger than one bound by silent obedience.

Mali is a Floating Gardener assigned to the Sea of Stories. Composed entirely of interlaced vegetation, he performs a function similar to a literary editor, untwisting tangled story streams and maintaining the health of the ocean's narratives.

Mr. Buttoo is an arrogant and heavily guarded politician operating in the Valley of K. Lacking genuine popularity, he hires celebrated storytellers to perform at his rallies in hopes of winning over the unenthusiastic crowds. He escorts his guests across the Dull Lake on a swan-shaped boat.

Bagha is a massive Plentimaw fish living in the Sea of Stories. His body is covered in dozens of mouths, which he uses to consume and filter the story streams. He suffers physical illness as dark poisons begin to pollute his aquatic home.

Goopy is a Plentimaw fish whose skin is dotted with numerous mouths. Alongside his partner, he constantly filters the magical currents of the ocean. He falls sick when the waters are contaminated by an enemy's dark acid.

Oneeta is the wife of Mr. Sengupta. She lives in the apartment above the Khalifa family in the sad city until her husband abruptly leaves her behind to elope with Haroun's mother.

King Chattergy is the elderly monarch of Gup City, the bright half of the moon Kahani. He presides over a kingdom that values constant talking, debates, and the endless spinning of tales, though his power is largely ceremonial compared to his military leaders.