Set in the 1920s, the film follows journalist Charles Anderson, who is deeply entrenched in covering the highly publicized Scopes Monkey Trial in Dayton, Tennessee. The trial revolves around a young schoolteacher, John Scopes, who is accused of unlawfully teaching evolution in his class, challenging the Tennessee law that mandates the teaching of creationism. Charles, eager to make a name for himself in a national debate, finds his professional and personal principles tested as he navigates through sensational journalism and the moral complexities of the trial. Assisted by his fiancée, Rose, Charles faces pressure from his editor and the influential figures involved in the trial, such as William Jennings Bryan and Clarence Darrow, who represent the opposing sides in a clash between science and religion.

As the trial progresses, the town of Dayton becomes a heated battleground for ideological conflicts, drawing public attention and media frenzy. The increasing tension causes Charles to question his own beliefs and the impact of sensational reporting on public opinion and justice. Charles and Rose's relationship is further strained as they encounter the ethical dilemmas posed by their roles in such a pivotal event. With both personal and professional stakes high, Charles must decide where his true loyalties lie while navigating the fierce environment of 1920s American journalism and the epoch-defining trial that has the whole nation watching.