Under the harsh glare of the military regime led by President Chun Doo-hwan, a student activist named Park Jong-chul, [Yeo Jin-goo], dies during an interrogation. A ruthless commissioner, Park Cheo-won, [Kim Yun-seok], oversees the investigation and tries to bury the truth by cremating the body and reporting the death as a heart attack. Park Cheo-won’s men press a drunken Prosecutor Choi Hwan, [Ha Jung-woo], to authorize the cremation, but he refuses to bow to their pressure. Despite his resistance, the autopsy goes ahead, with Jong-chul’s uncle, [Jo Woo-jin], standing nearby; the grim fate of the young activist becomes impossible to ignore.
The autopsy exposes a harsher reality than the official report suggested: the death was by asphyxiation, not cardiac arrest. The uncle steps outside the hospital to publicly announce the findings, and Prosecutor Choi, after facing dismissal, leaves behind crucial autopsy records for Yoon Sang-sam, a determined reporter, [Lee Hee-jun], who vows to pursue the truth despite a country-wide clampdown on reporting. Yoon’s discoveries begin to unravel the lies and point toward a deliberate cover-up orchestrated at the highest levels.
As public outcry swells, Commissioner Park decides to throw two detectives under the bus to bear the blame. He offers leniency to [Park Hee-soon]’s character, Detective Jo Han-kyung, in exchange for accepting involuntary manslaughter rather than murder, but the arrangement falls apart as Jo confronts colleagues and the system in a series of tense prison visits. In the shadows, guard Han Byung-yong, [Yoo Hai-jin], whispers of activism and tries to pry loose the visitation records that could prove the cover-up. His niece Yeon-hee, [Kim Tae-ri], a college student who helps him relay messages yet remains wary of politics, finds herself swept into the clash between protesters and police during a campus confrontation.
On the campus, Yeon-hee encounters a student activist and then watches footage of the Gwangju uprising during a club meeting, though she stays hesitant about joining the cause. The warden, moved by escalating threats, finally agrees to release the visitation records, but Park’s men trace the trail and seize the evidence before it can reach a wider audience. Yeon-hee initially hesitates to hand the records to Han, but she ultimately becomes a conduit to the truth. The records reach the Catholic Priests’ Association for Justice, who issue a public statement revealing that Park Jong-chul was killed during interrogation under direct oversight, with Park Cheo-won having orchestrated the attempt to conceal the crime.
A flashback deepens the tragedy: Jo Han-kyung is taunted by the dying memory of Jong-chul, while Park Cheo-won’s influence extends into the political sphere, revealing that President Chun had green-lit the arrest and the attempt to pin the death on others. Han is released and reunited with his family, but the toll of the case lingers. Meanwhile, Yeon-hee finally sees the broadening impact of the movement when a photograph shows activist Lee Han-yeol, [Gang Dong-won], severely wounded at a protest and later killed by a police tear-gas canister. The sight devastates Yeon-hee, catalyzing her decision to dedicate herself to the democracy movement and to stand with those who seek accountability and change.
