In 1934, underground Party member Xiang Yunian carried the top-secret intelligence of the "Iron Bucket Plan" and set out from De'an in northern Jiangxi for Ruijin, the Central Soviet Area. Along the way, Xiang Yunian passed through checkpoint after checkpoint and perilous surroundings, witnessing with his own eyes all walks of life in a chaotic age. In the end, he resolutely knocked out his front teeth, disfigured his face and disguised himself as a beggar, risked his way through the checkpoints, and completed his mission in full. The Central Red Army evacuated before the enemy's encirclement was completed and embarked on the long 25,000-li march.