In 1945, Harbin has come under the rule of Japan's puppet state known as Manchukuo. Communist agent Song Zhuo Wen successfully infiltrates Harbin Secret Service where Guan Xue holds a post as the chief of special police.

The vacationing policeman stays at the "Five Incense" homestay, where there are also detective novelists, vagabonds, and a pianist played by Cao Enqi. With the death of the homestay owner and the waitress, the identities of all the people in the homestay are suddenly unclear. All are suspects, and all are detectives. The "Five Incense Homestay" is filled with mystery overnight.What unknown secrets...