October 26, 1979, a presidential assassination shakes the nation.

"If this was going to happen, why bother with a trial?" Taking on the defense of Park Tae-joo, the secretary involved in the presidential assassination, lawyer Jung In-hoo enters what would be South Korea's most notorious political trial. Despite Park Tae-joo facing a predetermined sentence due to his military status, Jung In-hoo fights tirelessly to ensure a fair trial, enraged by the trial's unfair proceedings.

"Am I supposed to sacrifice you just to save myself?" Thirty minutes before the incident, Park Tae-joo, instructed by the intelligence chief to suppress his bodyguards in case of trouble, faces scrutiny in court over whether his actions were preemptive treason or mere obedience to orders under duress. Jung In-hoo proposes a testimony that could potentially exonerate Park Tae-joo, but Park insists on maintaining his moral integrity.

"No matter what you do, he must die." Meanwhile, following the events of October 26, Deputy Director Jeon Sang-du harbors dangerous ambitions. He mocks the confident Jung In-hoo, eavesdrops on the trial, and effectively manipulates the court by passing notes to the judges in real-time.

Between October 26 and December 12, unfolds the worst political trial in South Korean history, a tale of ambition, betrayal, and justice.