It is 1957, and twelve men have been led into a jury room of a New York City court of law. They are given final instructions about determining the verdict in a murder case whose defendant faces the death penalty if found guilty.
Before deliberations begin, the men take a short break after filing into the hot and stuffy room. They gather around a long table to begin discussions about the case. The defendant, a young man, is accused of killing his father; and, after a preliminary vote, all but one of the jurors presume he is guilty. Juror #8 is the only one who feels differently. Because they must come to a unanimous decision, debates begin. Most of the men are upset and very vocal about the dissenting vote.
It is agreed to go around the table and have each man explain why he believes the young man is guilty, in hopes of convincing Juror #8 to change his mind. They heatedly discuss the known facts of the case; and little by little the personalities, opinions, and biases of each juror become evident. Subsequent votes are taken, and each time there are less and less who still believe the defendant is guilty.
Eventually Juror #3 is the only one left who maintains his original “guilty” vote. He is determined to holdout and make it a hung jury. Will this last juror obstinately stand his ground or can the others convince him otherwise?