In the turbulent late Sui Dynasty, Li Shimin, the young Prince of Qin, faces a miraculous and bewildering event when his wife, Changsun Wuyou, gives birth prematurely to an egg instead of a human infant. The egg, adorned with dark gold patterns resembling formation talismans, exhibits signs of life and a profound spiritual connection to its parents. Li Shimin, initially in shock, seeks answers and is visited by the Daoist priest Yuan Tiangang, who reveals that the child is a divine dragon born to shape the fate of the realm. Yuan Tiangang provides a spiritual needle to nourish the egg with Li Shimin's essence blood, instructing him to keep the child close to stabilize its spirit until it hatches.
As Li Shimin prepares to lead the Tang army against the rival warlord Xue Ju, he conceals the egg within his armor, protected by a magical mirror. Inside the egg, the unborn child, who identifies himself as Ying Zheng, navigates his new existence in the mortal realm, which lacks the spiritual energy he is accustomed to. Hungry and vulnerable, Ying Zheng relies on his father's essence blood for sustenance. When Li Shimin falls gravely ill with malaria before the battle, Ying Zheng’s spiritual awareness awakens fully, sensing the danger to his father and the chaotic demonic energies surrounding the battlefield.
The conflict escalates when Li Shimin’s deputy generals, Liu Wenjing and Yin Kaishan, disobey orders and launch a reckless attack on Xue Ju’s forces at Shallow Water Plain, resulting in a devastating defeat. With the Tang army in disarray and Xue Ju’s forces pursuing them, Li Shimin, despite his illness, leads a small elite cavalry unit to rescue his troops. During the retreat, Ying Zheng, anxious and protective, exerts his power to sustain his father’s life force. In a moment of crisis, as a demonic Fei beast approaches Li Shimin’s tent, Ying Zheng bursts from the egg, transforming into a colossal divine dragon and swallowing the monster whole before reverting to his naked infant form.
The birth of the dragon child coincides with the arrival of the renowned physician Sun Simiao, who is treating the plague affecting the army. Sun Simiao’s presence introduces further mystical elements, as he recognizes the extraordinary nature of Li Shimin’s child. The narrative explores the intersection of historical warfare and mythological fantasy, with Li Shimin balancing his military duties against the secret care of his divine offspring. The story highlights the growing bond between father and son, as Ying Zheng learns to navigate his new identity while Li Shimin prepares for the challenges of founding the Tang Dynasty. The egg’s hatching marks a pivotal turning point, signaling the emergence of a powerful entity destined to influence the course of history, while Li Shimin must now protect his child from the political intrigue and supernatural threats that surround them.
