Once upon a time in Cao Binh district, there was an elderly couple who had no children. Seeing that they were kind, Ngoc Hoang sent the crown prince to reincarnate as a child. The boy was born without a father, and later his mother also died. Since then, he has lived in seclusion in the banyan tree, the whole fortune is left only by the hammer left by his father, people call him Thach Sanh.

One day, Ly Thong passed by and saw Thach Sanh carrying a large bundle of firewood. Seeing that Thach Sanh was in good health, Ly Thong started to talk to the two of them so that they could be sworn brothers. Thach Sanh stayed with Ly Thong's mother and daughter. Now, in the area there was a fierce ogre, who forced the villagers to give him a human life each year. That year, it was Ly Thong's turn. That afternoon, Ly Thong waited while Thach Sanh went to collect firewood to prepare a plate of wine and meat, and then said:

- Tonight it's my turn to watch the shrine, so I'll take the trouble to replace you for one night, come back in the morning.

Thach Sanh did not have any doubts and agreed to go immediately.

At midnight that night, Thach Sanh was half-closed eyes when an ogre appeared to pounce on him. Thach Sanh used a variety of martial arts to beat the monster. It wasn't long before his hammer tore it in half. Thach Sanh cut off the monster's head and brought it back. When they returned, Ly Thong's mother and daughter were very scared. But after listening to Thach Sanh recount, Ly Thong immediately said to him:

- It's the king's pet, killing it is a crime. Well, since it's not morning yet, let's hide now.

Thach Sanh believed Ly Thong and fled. Ly Thong took the opportunity to bring the ogre's head to the king. The king praised him and made him an admiral.

Speaking of princesses of marriageable age. On the day of the cocoon, the princess was carried away by a giant eagle. Thach Sanh immediately shot the eagle with a bow and arrow and traced the blood trail to find its whereabouts. Ly Thong was sent by the king to find the princess. Thach Sanh told Ly Thong about the eagle's cave. The two go to save the princess. Go to Thach Sanh cave, please go down to the cave to save the princess. Thach Sanh fights with the eagle, saves the princess. He was waiting for his turn to go up when he did not expect that Ly Thong had ordered his soldiers to fill in the cave with large stones, then pull each other back.

Thach Sanh went around the cave to find a way out. He went to the end of the cave and saw a young man locked in an iron cage. Thach Sanh used a bow and arrow to destroy the iron cage to save the boy, who was the son of King Thuy Te. He was invited to go to the water palace to play, treat him well, and then bring him back to his hometown.

When he returned, he was harmed by the spirits of the ogre and the eagle, so he was imprisoned. After the princess was rescued, she did not speak or smile. In the prison, he took the guitar given to him by King Thuy Te and beat him to express his injustice. The princess heard the piano and spoke. The king was surprised that Thach Sanh came to see him, he told all his injustices. Ly Thong was punished and Thach Sanh was allowed to marry the princess.

Seeing the jubilant wedding ceremony, the princes of the former vassal countries were kissed by the princess and sent troops to fight. Thach Sanh took out the lute to play, the sound of his lute was just played, causing the soldiers of the eighteen countries to beg their hands and feet to surrender. Challenge Sanh ordered to cook rice for a treat, the soldiers couldn't finish the tiny pot of rice, thanked each other, and then dragged each other back to the country. Later, the king had no son, so he ceded the throne to Thach Sanh