The Gwangju Uprising in 1980, known as 5.18 or May 18, is regarded as singularly pivotal for the democratization of South Korea. To oppose the military coup staged by South Korean Army General Chun Doo-hwan, ordinary citizens joined student protesters in a popular uprising that lasted ten days until a brutal military crackdown resulted in a civilian massacre. This chapter explores the meaning of rediscovered photographic and video evidence from the uprising which has only recently been made public. It highlights how transitional justice remains incomplete yet highly relevant to defend against specious claims made by ultra-rightists who deny the Gwangju massacre. Adding to recent forms of May 18-related memory activism—such as artistic work, screenings of recovered footage and mediated advocacy among the global fandom of K-pop group BTS—these developments highlight the importance of responding to controversies over historical redress not only through formal institutions like fact-finding commissions but also in cultural realms and the vernacular public sphere.