The message

Plot

April 26, 1940, former Nationalist vice president Wang Jingwei made peace with Japan and set up a Japanese-supported regime during World War II, a puppet government in Nanking. Oct 10, during an anniversary ceremony of the government, a Wang government high official was assassinated, the last in a series of such attacks. Wang Tianxiang, thWang Government's intelligence chief (Litian Zhou) believed that it was an action of an underground anti-Japan group and that there was a mole, nicknamed "Old Ghost" (aka The Phantom) inside the Wang government's Anti-Communist Command.

Determined to catch the mole, Taketa sends out a telegram with false information about an opportunity to assassinate a high ranking officer. When it is apparent that the underground group knows its contents, he arrests the five personnel who saw the telegram, bringing them to the closely guarded fortress Qiu Castle for interrogation. They are: (1) Anti-Communist squad captain Wu Zhiguo (Zhenyi Xu), (2) Bai Xiaonian (Bian Ge), an aide to the commander, (3) chief telegraph decoder Li Ningyu (Ziyu Wang), (4) mailroom staff Gu Xiaomeng (Mengzhen Lian), and (5) military intelligence director Jin Shenghuo (Runmin Xiao).

Wang Tianxiang need to identify "Old Ghost" in five days. After the suspects are tormented by constant interrogations, they began informing against each other for their own survival. Increasingly horrific physical tortures are used as the interrogators become impatient, while the tormented suspects come close to losing their sanity. A tense game of "cat and mouse" ensues as the Chinese espionage agent attempts to send out a crucial message while protecting his/her own identity.