Disillusioned knight Antonius Block (Max von Sydow) and his nihilistic squire Jöns (Gunnar Björnstrand) return after fighting in the Crusades and find Sweden being ravaged by the plague. On the beach immediately after their arrival, the knight encounters Death (Bengt Ekerot), personified as a pale, black-cowled figure resembling a monk. The knight, in the middle of a chess game he has been playing alone, challenges Death to a chess match, believing that he can forestall his demise as long as the game continues. Death agrees, and they start a new game.
The other characters in the story, except for the squire, do not see Death, and when the chess board comes out at various times in the story, they believe the knight is continuing his habit of playing alone.
Death and Antonius Block choose sides for the chess game; Death gets the black pieces.
The knight with his squire heads for his castle. Along the way, they pass some actors, Jof (Nils Poppe) and his wife Mia (Bibi Andersson), with their infant son, Mikael, and their actor-manager, Skat (Erik Strandmark). Jof is also a juggler and has visions of Jesus and Mary, but Mia is skeptical of them.
The knight and squire enter a church where a fresco of the Dance of Death is being painted. The squire draws a small figure representing himself. The knight goes to the confessional where he is joined by Death in the robe of a priest, to whom he admits that his life has been futile and without meaning, but that he wants to perform "one meaningful deed."[7] Upon revealing the chess strategy that will save his life, the knight discovers that the priest is Death, who promises to remember the tactics. Leaving the church, the knight speaks to a young woman (Maud Hannson) who has been condemned to be burned at the stake for consorting with the devil.
Shortly thereafter, the squire searches an abandoned village for water. He saves a servant girl (Gunnel Lindblom) from being raped by a man robbing a corpse. He recognizes the man as Raval (Bertil Anderberg), a theologian, who 10 years prior had convinced the knight to leave his wife and join a crusade to the Holy Land. The squire promises to brand the theologian on the face if they meet again. The servant girl joins the squire. The trio ride into town, where the actors met earlier are performing. The actor-manager introduces the other actors to the crowd, then is enticed by Lisa (Inga Gill), the blacksmith's wife, away for a tryst. They run off together. The actors performance is interrupted by the arrival of a procession of flagellants.
At a public house, the juggler meets the theologian who forces him to dance on the tables like a bear. The squire appears and, true to his word, slices the theologian's face.[8] The knight enjoys a country picnic of milk and wild strawberries gathered by the wife of the juggler. The knight says: "I'll carry this memory between my hands as if it were bowl filled to the brim with fresh milk...And it will be an adequate sign – it will be enough for me."[9] He invites the actors to his castle, where they will be safer from the plague.
Along the way, they come across the actor-manager and the blacksmith's wife in the forest. Dissatisfied with him, she returns to her husband. After the others leave, the actor-manager climbs a tree for the night. Death cuts down the tree, informing the actor that his time is up.
They pass the condemned young woman again. The knight asks the woman again to summon Satan, so he can ask him about God. The girl claims already to have done so, but the knight cannot see him, only her terror. He gives her herbs to take away her pain.[10]
The theologian reappears. Dying of the plague, he pleads for water. The servant girl attempts to bring him some, but the squire stops her. The juggler tells his wife that he can see the knight playing chess with Death, and decides to flee with his family while Death is preoccupied.[11]
The final scene depicting the "danse macabre".
After hearing Death state "No one escapes me" the knight knocks the chess pieces over, distracting Death while the family slips away. Death places the pieces back on the board, then wins the game on the next move. He announces that when they meet again, the knight's time—and that of all those traveling with him—will be up. Before departing, Death asks if the knight has accomplished his one "meaningful deed" yet; The Knight replies that he has.
The knight is reunited with his wife, Karin (Inga Landgré), the sole occupant of his castle, all the servants having fled. The party shares one "last supper" before Death comes for them. The knight prays to God, "Have mercy on us, because we are small and frightened and ignorant."[12]
Meanwhile, the little family sits out a storm, which the juggler interprets to be "the Angel of Death and he's very big." The next morning, the juggler, with his second sight, sees the knight and his followers being led away over the hills in a solemn dance of death.