John Brown and his sons fight to make Kansas a free state and then go to Harper’s Ferry to try to instigate a slave revolt.
In 1856 men go to Kansas territory to determine whether it will become a free state or a slave state. Oliver Brown (Larry Pennell) and Owen Brown (Jeffrey Hunter) are on a train. They meet some ruffians from Missouri and are about to fight when pretty Elizabeth Clark (Debra Paget) tries to talk them out of it; but she begins a scuffle by slapping one of the ruffians. The brothers persuade the two men to leave the car. She introduces herself to Oliver and Owen. They are going to Lawrence.
They arrive in a wagon and are met by Frederick Brown (John Smith). Elizabeth learns they are the sons of John Brown, and she does not want to have anything to do with him. John Brown (Raymond Massey) arrives and meets her. The Browns leave town in a wagon. Elizabeth is welcomed by her father, who says John Brown is a great man.
In a camp with tents men are building a church. John Brown Jr. (Dennis Weaver) and Salmon Brown (Guy Williams) greet their arriving brothers. John says they have work to do. Green (James Edwards) notices some men riding toward them. John tells some to get their guns. Martin White (Leo Gordon) meets John Brown and warns him to leave because he considers him a dangerous traitor. John says he and those with him are homesteaders. White sees rifles pointed at them and says they will have bloodshed if they want it. John says there will be no bloodshed there unless others start it. White and his men ride off. John assures Owen and Oliver that he has guns for them.
Elizabeth tells Owen that she likes him, but she does not want it to be serious. She questions the methods of his father. Owen says she is wrong. He admits he has fallen in love and kisses her.
White speaks to a dozen men, and they ride off at night to teach a lesson. They ride to town and throw barrels in the buildings and then use torches to set them on fire, shooting a man who tries to make a warning sound. They also shoot a man and a woman and then another man. Elizabeth comes out and sees her father is dead.
In their camp John and his sons pray before eating. Kruger arrives in a wagon with Elizabeth and tells John that five people were killed in Lawrence. John tells them to prepare for those coming from Lawrence, and they plan to leave. Kruger writes down the names of White and others he identified. John says they are leaving at once with guns. They break into a house and abduct the father and two grown sons. John tells them to strike the blow of the Lord, and they kill the three men. John Jr. asks how he knew they were guilty, and John says they were seen at Lawrence.
When John and his men return to the camp at Osawatomie, they see a wagon train about to leave; but he persuades them to stay and put their tents back up. Elizabeth tells Owen that John is a murderer and that he made Owen one too. John Jr. wants to turn himself over to the United States Army, and Jason Brown (James Best) is going to help him. They leave, and then Frederick says he is going away to be alone for a while. Owen says they have to stay with their father, and his brothers ask him to talk to his father about the killing. Owen tells his father that what they did that morning was wrong. John says he gives the orders, and he calls his son weak and cowardly.
White and another man find Frederick under a tree and tell him they are organizing men to fight John Brown. Frederick declines to join them. White recognizes him and kills him.
At the camp they see many horsemen on a hill and prepare. About twenty riders approach and begin shooting. The Browns shoot back from behind wagons and kill several. John orders them to fall back to the woods and keep firing. The men tear down the tents and the church structure. White approaches and shoots Owen, but they kill him. A doctor treats Owen but tells John he will not come back because he has a family. Elizabeth takes care of Owen despite John’s objection. John tells the others they have not destroyed what they came for, which is to vote.
They rebuild. Elizabeth takes food to Owen, who is sitting up and kisses her. He says he loves her, and she admits she loves him. She says she hates violence, but she can’t help loving him. He says they will get married. She wants to go away from there. Salmon and Oliver tell Owen that they are leaving, but Owen says he is staying with his father. John comes in and forbids them to leave. Oliver tells his father he has failed. He says they will die because of his stubbornness. John slaps him, and Oliver asks to be forgiven. Oliver and Salmon say goodbye.
Owen and Elizabeth discuss the voting. He wants to get married, but she wants to discuss things. Owen says they are going home to Ohio to his farm, and she agrees with that. They see John returning, and he says they won, making Kansas a free state. Owen says they are getting married and going home. John gives them his blessing.
In a house John prays before dinner with their mother and their living sons. John Jr. says he does not want to be sick again. Their mother says it has been two years since they were together. John Jr. and Jason promised the army they would not ride with their father anymore. Young Watson Brown (Tom Irish) says he will be with his father. Owen says so too, and Elizabeth is upset.
At Boston in 1858 Henry David Thoreau and others question John Brown about his plans. Brown says he will not explain his cause, and an elderly gentleman donates $1,000. John buys rifles and has them marked as farm machinery and sent to Harper’s Ferry, Virginia.
Wilson and Thompson men come to Owen’s farm. Green and another Negro also arrive. Elizabeth asks Owen why he is keeping his plans secret. He says she and the world will find out.
John talks to about a dozen men and says slaves will rise and join them. He says they must not harm the hostages so that they can trade them. John kisses his wife. Owen, Oliver, and Watson kiss their mother. Elizabeth sees it as the end, but John says it is a beginning. Owen tells her he loves her, and they kiss before he goes.
The men walk, and Owen and Green drive the wagon on another road. They break into a building and destroy the telegraph. John Brown tells a black employee that he came to free them by taking over the arsenal. The black man says he is free, but he is knocked out. They grab a watchman, and John gets the keys to the arsenal. They capture five men, and John says the men will be allowed to leave later. Brothers bring in Col. Louis Washington (Robert Simon) and a few other prisoners. Washington tells Brown he will hang, and John says he will be remembered for it.
A man arouses people in the town. Lt. Col. Robert E. Lee is told that Brown and eighteen men have taken over the arsenal to free the slaves. They have cut the telegraph wires at Harper’s Ferry. About a dozen men in the town are armed with rifles and take positions.
John is told they are surrounded. He sends Watson with a white flag to tell them he does not want bloodshed; he wants to trade the hostages for slaves. As they go out, one hostage runs out and is killed. Then Watson is shot and is brought back in wounded. A gun battle begins. John says he does not expect the slaves until the next morning.
In another building Green tells Owen that he does not think any colored folk are coming. Wilson says he is leaving, but Green stays with Owen.
Watson dies, and John asks if the Lord has forsaken him. Washington says at least the one killed will not hang. Oliver goes to a window and is killed. John says he will go on so that all men shall be free.
Col. Lee leads about twenty men who march double time. Owen says he is going to help his father, but Green stops him by saying his father is finished. Owen and Green walk out on to a road out of town.
John says they are coming to bargain. Two soldiers approach with a white flag. Lt. Jeb Stuart conveys a message from Col. Lee, demanding their surrender. John asks for terms, but Stuart says the only terms are surrender or be taken. Stuart reports to Lee that Brown refuses to surrender. The soldiers are deployed, and some are shot. Others use a battering ram to break in the door. John Brown is shot but is not killed. Lee frees the hostages.
A judge says John Brown is charged with treason, conspiring with slaves and others to rebel, and murder in the first degree. An attorney reads a statement that Brown’s family is insane. John declares that he is not insane, and he objects to this interference. The judge asks him to make a statement before sentencing. John says he has interfered on behalf of God’s despised poor. He is willing to forfeit his life for justice along with his sons who have died. The judge sentences him to death on December 2, 1859 by hanging.
Owen and Elizabeth visit John in jail. Owen says he is in touch with abolitionists who will help him to break him out of jail. John says no but is glad they believe in him. He says he will be worth more by hanging. They embrace.
John Brown is bound by a rope and walks as the drum rolls. He mounts the platform of the gallows, and the “Battle Hymn of the Republic” is heard.
This historical drama accurately portrays the zealous John Brown who led his family in a crusade to free slaves in the United States. John Jr. and Jason were actually captured by Missourians. A free black man was killed at a train station. Four other men were hanged with John Brown, and two others were hanged in 1860.