When the chaos first opened, the world's first demon came into the world, named Yuandi, and was regarded as the demon ancestor. Millions of years later, the former demon king Sun Wukong was rescued by Tang Seng from the foot of the Five Elements Mountain. Wukong promised to protect Tang Seng and go to the West to learn the scriptures. And the legendary demon ancestor Yuandi once again appeared, and the Three Realms were at stake. The two generations of Demon Kings are destined to fight the ultimate battle, but this time, Monkey King meets a real rival.