The thirty-seventh chapter mainly tells the story of Tang Priest and his disciples meeting monsters in the infinite country. King Wuji was killed by the lion's tail monster for fighting with it, and his body was soaked in the well. The frog fairy in the well told the Tang Priest that the old gentleman had a disciple named "King of the Promise" who was killed by him because he failed to fight the lioness monster, and his body was soaked in the well. Frog Fairy told Tang Priest that if he wanted to save the King of the Infinite, he needed to ask Grandpa Laojun for help, because the lioness monster was his apprentice.
Tang Priest and his disciples came to Taishang Laojun Temple and asked Taishang Laojun for help. The old man told them that the lion-tailed monster was his apprentice and was driven out of the Heavenly Palace because he stole his treasure. But Grandpa Laojun also told them that if you want to save the infinite king, you need to find Hong Haier first, because Hong Haier is the nemesis of the lion-tailed monster.
The Tang Priest and his disciples came to a mountain peak and met Hong Haier. Hong Haier disguised himself as a child and fooled the Tang Priest and his disciples. However, the Monkey King discovered the true face of Hong Haier, and the two men fought fiercely. In the end, the Monkey King outwitted Hong Haier and rescued the King of the Promise.