The first section of the story deals with the Monkey King, a trickster who rebels against heaven and its celestial deities, as he thinks himself stronger and more deserving of divine power than any other. Ultimately, only Buddha can contain him. The author says:

The dear Great Sage hurriedly braced himself to jump, but the Buddha turned his hand over and pushed the Monkey King out through the Western Gate of Heaven. He turned his five fingers into a mountain chain belonging to the elements Metal, Wood, Water, Fire, and Earth, renamed them the Five Elements Mountain, and gently held him down.

The Monkey King stays there for five hundred years, until a monk, the novel’s protagonist, Tripitaka, is sent to retrieve him as a companion on the journey to return the Buddhist scriptures from India to China. Along the way, the Monkey King has to earn forgiveness for his actions in the past.

Characters in the story are punished or rewarded for their deeds. For example, the monk's father is thought to have been killed by a ferryman, who usurped his wife and title. After the man's crimes are revealed and he is executed for his guilt, the monk's father appears. He says,

It is all because we bought and released that golden carp when we were staying at the Ten Thousand Flowers Inn: the carp, it turned out, was the local dragon king. When that treasonous murderer pushed me into the water I was rescued by the dragon king, who has given me back my soul and presented me with all the treasures I have on me. I never had any idea that you had borne this son, or that my father−in−law had avenged me. Our sorrows are now at an end. This is a very happy moment indeed.

Because of their faithfulness and kindness, the family is reunited after long years apart. If they hadn't kindly released the carp who happened to be the dragon king, the father would have died when the ferryman attempted to murder him.

The travelers are helped along by various deities in their quest. The things they face are beyond the comprehension of mortal people and may have been impossible to face without the strength and magic of the monk's companions. The author says,

"I personally asked the Jade Emperor to put the dragon here as a mount for the pilgrim," said the Bodhisattva. "Do you think an ordinary horse would be able to cross the thousands of mountains and rivers to reach the Buddha−land on the Vulture Peak? Only a dragon horse will be able to do it."

When the monk first meets the dragon, the dragon eats his horse; he is unaware of the monk's identity. He has to transfigure himself into a horse to serve the people on the journey.

At the end of the story, each of the people on the journey receives a station in paradise as a reward.

"Holy Monk," the Tathagata said,"in an earlier life you were my second disciple, and called Master Golden Cicada. But because you would not listen to my sermon on the Dharma and had no respect for my great teaching I demoted your soul to be reborn in the East. Now, happily, you have come over to the faith and rely on our support; and in following our teaching your achievement in fetching the true scriptures has been very great. Your reward will be to be promoted to high office as the Candana−punya Buddha."

The characters' lives were each changed because of their sins and transgressions. Only the journey and the redemption they earned by bringing the Buddhist scriptures back to China can—and does—offer redemption. The Monkey King also becomes a Buddha. Their other companions receive lesser stations suited to their personalities and desires. For example, Pig becomes an Altar Cleaner because of his voracious appetite.