The son of a freedom fighter, Sang-hun is a member of an anti-Japanese resistance group called "Seongjinhoe," composed of students who share a dedication to the cause of liberation. Their spiritual guide is a teacher named Song Un-in. One day, Yeong-ae, whose brother is a detective in the Japanese police force charged with monitoring independence movements, joins their group. Following a series of sporadic incidents, the students gather one night to resolve on an uprising, but are discovered by the police. Young-ae is wrongfully accused of betraying their plans, but she risks her life in order to allow the group members to escape. The morning after, the students of Gwangju rise up against the Japanese government.
This film is about of the life of the young patriotic martyr Yu Gwan-sun, who fought for the liberation of her country during the Independence Movement in 1919. As the Independence Movement becomes more and more intense among Korean students, the Japanese authorities order schools closed temporarily. Yu Gwan-sun (Do Geum-bong) persuades her neighbors to join the national movement, and continues her aggressive struggle against Japanese rule. An independent campaign at Aunae, a market site, is successful with the passionate participation of many people. She is arrested by the Japanese police for leading the campaign and has to endure horrible tortures. But she never gives up her fight, encouraging her cell mates to participate in the movement. She is finally taken to an underground room by the Japanese police and murdered.