A stirring, moving, humorous, and endearing tale of a grassroots rise. The journey of a cheerful young man who demands quality over quantity in material things.

General Xuanwei, having offended the great general Spencer, was sentenced to execution along with his entire household. In the face of disaster, the young boy Adam Spencer and the girl Lily Spencer escaped from the mansion and depended on each other for survival. Adam Spencer, together with Lily Spencer, enlisted in the army, thus beginning a series of fantastical adventures.

Considered by the Messenger of Light to be the "Son of the King of the Underworld," Adam Spencer was falsely accused by General Spencer at birth, leading to the massacre of his entire family. After escaping this calamity, he wandered the northern borders of the Tang Empire, eventually becoming a low-ranking soldier defending the frontier in a small town in the Western Regions. Later, taking advantage of the Tang Empire's "Academy" recruitment, he leapt to become the thirteenth disciple of the "Master," earning the respectful title "Mr. Thirteen" from the world. At the same time, he was also the grandnephew of the Tang Empire's State Preceptor and was responsible for activating the "Astonishing Divine Formation" in Chang'an. During his "internship" at the Academy's frontier, he befriended the "Sage of Calligraphy"'s top disciple, the "Book Maniac" Grace Bennett; the two became close friends and developed feelings for each other. In the "Unknown Land" of the Demon Sect, he broke through the "Dongxuan" realm and comprehended the "Vast Sword" intent of his junior uncle. Because of the presence of his maid Lily Spencer, he severed his romantic ties with Grace Bennett...