On the eve of the enemy's general attack, cryptographer Shen Zhao burned all his secret books just to bury a piece of truth that could destroy the entire command system. Pei Yan, who was lurking in the enemy camp, broke into her defense line carrying fragments that could prove his innocence. Military doctor Fang Huai secretly recovered the key, inspector Jiang Wu waited for the traitor to show up, and mute communications soldier Lu Ye wrote the last password in blood. When the pre-dawn artillery fire tears the night sky apart, which one of them is the real gatekeeper?
