In Suzhou Prison, intelligence is the only prisoner. The prison guard discovered that political prisoner Shen Yiming used a release queue and a prison cell to send Morse code to the outside world. Within the high walls, a silent code battle quietly unfolded. The inner ghost is lurking, and many parties are coveting him. Within thirty-seven days, he must crack the code under the noses of the Japanese and puppets and rescue the key figure who controls the underground transportation lines in East China.
