He justifies himself before King Fernando, relating with quiet dignity, how he killed Count Lozan in open duel to avenge his old father, whose honour the Count had grossly attacked. Nevertheless he is ready to defend himself against anybody, who is willing to fight for Donna Chimene, and for this purpose he throws down his glove, which is taken up by Alvar Farnez, his friend and companion in arms, who is madly in love with Chimene.—While they are preparing for the duel the Bishop Luyn Calvo, an uncle of Diaz, intervenes, entreating his nephew to desist from further bloodshed and to surrender his sword Tizona into his the priest's hands. After a hard struggle with himself the hero, who secretly loves Chimene, yields, and hands his sword to Calvo, who at once offers it to Chimene, thereby giving the defenceless hero into her hands.
Exultingly she swears to take vengeance on Diaz, who stands motionless, looking down with mournful dignity on the woman whom he loves and who seems to hate him so bitterly.
In the midst of this scene the war cry is heard. The enemy has again broken into the country and has already taken and burnt the fortress of Belforad. All crowd round Diaz, beseeching him to save them. While he stands mute and deprived of his invincible sword, Chimene, mastering her own grief at the sight of her country's distress, lays down Tizona at Fernando's feet. Ruy Diaz now receives his sword back from the hands of the King, and brandishing it high above his head he leads the warriors forth to freedom or death.
The second act takes place in Chimene's castle. Her women try to beguile their mistress's sorrow by songs, and when they see her soothed to quiet, they retire noiselessly. But hardly does she find herself alone than pain and grief overcome her again. She longs to avenge her father's death on Diaz, and yet deep in her heart there is a feeling of great admiration for him. In vain she wrestles with her feelings, invoking the Allmighty's help to do what is right. In this mood Alvar finds her and once more assures her of his devotion and repeats that he will fight with Diaz as soon as the country is freed from the enemy. He leaves her and night sets in and in the darkness Diaz steals in, for he cannot resist his heart's desire to see Chimene once more before the battle. In the uncertain rays of the moonlight she at first mistakes him for her father's ghost, but when he pronounces her name she recognizes him, and violently motions him away, but he falls on his knee and pours out his hopeless love. At last his passion overcomes all obstacles; she forgives him and at his entreaty she calls him by his name, saying: "Ruy Diaz be victorious!" Full of joy he blesses her and goes to join his men who are heard in the distance calling him to lead them to battle.
The third act is played once more in Burgos.
Diaz has been victorious; the whole army of captives defiles before the throne and a rejoicing assemblage of nobles and peoples does homage to the King. Even the Moorish Kings bend the knee voluntarily; they have been unfortunate, but they have been conquered by the greatest hero of the world; they are conquered by "the Cid!" When the King asks them what the name means they tell him that its signification is "Master"; full of enthusiasm all around adopt this name for their hero. The Cid will be Diaz' title henceforth, immortal as his glorious star!
The people loudly call for Diaz to appear, but are told that immediately after the battle Alvar had sent the hero a challenge. At the same time Alvar enters unhurt, and Chimene who stands near the King with her women ready to greet the victor, grows white and faint, believing that Diaz has been killed by Alvar. She impetuously interrupts the latter, who begins to relate the events, and unable to control her feelings any longer she pours out her long pent up love for Diaz, at the same time bewailing the slain hero and swearing faithfulness to his memory unto death.—"He lives" cries Alvar, and at this moment the Cid, as we must now call him appears, stormily hailed by great and small.
Deeply moved he lays down his victorious sword at the feet of his King, who embraces him pronouncing him Sire of Saldaja, Cardenja and Belforad. Then he leads him to his lady who sinks into his arms supremely happy. The Bishop blesses the noble pair and all join in his prayer, that love may guide them through life and death.