The plot of Journey to the West concerns Tang Sanzang's quest to bring Buddhist scriptures from India to China. Early in the narrative, the Emperor Taizong sends the monk Tang Sanzang on a pilgrimage to Leiyin Temple in India. As Tang Sanzang sets out along the silk road, he encounters various characters who join him on his quest as a way of atoning for their sins. These are Sun Wukong (the Monkey), Zhu Bajie (the Pig), Sha Wujing (the Ogre), and Yulong, the son of the Dragon King of the West Sea, who changes into a horse.
After Tang Sanzang has encountered his traveling companions, the main part of the story (chapters 23–86 out of 100) takes place on the actual journey to the West, during which the pilgrims encounter a succession of twenty-four antagonists, generally sorcerers or monsters. There are also geographical hazards such as flaming mountains and raging rivers. Having passed through all these perils, the companions reach India, where they find the Leiyin Temple and receive the scriptures from the Buddha. Although the journey to the West took fourteen years and was fraught with danger, the return trip to China is quickly described in the final chapter. Tang Sanzang and Sun Wukong both achieve Buddhahood on their return, and the other travelers receive lesser rewards.