The story tells that during the Republic of China, Zhang Xiaozhi, Qianyan and Yangling were threatened by the riot warlord Li Yufei and forced to go to the Shenlong Underground Palace to solve the thousand-year secret.
Unfortunately the movie Secret Army is not yet available on HBO Max.
| Writing | Ni Minming | Writer |
| Writing | Wang Chaoyuan | Writer |
| Directing | Liu Shu | Director |
