Great Tang: Thrown into Prison from the Start

In the ninth year of the Wude era, Li Rui, who had transmigrated from another world, was thrown into prison by Li Shimin.

By chance, he awakened the System and earned a sign-in reward in prison: Song Ci's forensic expertise.

After outsmarting the Tuyuhun spies, he officially entered the Tang dynasty's bureaucracy.

Li Jiancheng: "I'm Li Jiancheng, Crown Prince of the Tang dynasty. I'm freaking out. I feel like I'm about to lose my position as crown prince. What should I do? Anyone there? It's urgent!!"

Li Shimin: "I'm Li Shimin, Prince of Qin in the Tang dynasty. I'm not worried at all. The throne? I don't even want it."

Jieli Khan: "The heavens are so unfair!! If I'd known Li Rui was around, I would have submitted to the Tang dynasty ages ago!!"

Yeon Gaesomun: "Why would Heaven help the Tang army? Heaven wants me dead!!"

Songtsen Gampo: "I have long admired the Tang dynasty. I wonder if I might ask for your daughter's hand in marriage..."

Li Rui: "No, you don't."

This novel and its characters are entirely fictional. Any similarities are purely coincidental. Do not imitate.