After Lucas discovers that his wife, Reina, is having an affair with his partner and friend, he divorces her and leaves Puerto Rico with their young son Fernando. Placing Fernando in a boarding school, Lucas travels abroad for some time. But after gambling away most of his money, Lucas returns to San Juan.

Don Juan leaves Venice and gets back to Seville, his home city. When he arrives there, he learns that his father is dead and has left all his properties to him, on codition that he marries Doña Inés. Don Juan makes up a former marriage, but when he meets her he becomes fascinated by her beauty.

In 1922, Infantry Captain Fernando Salas, arriving from Madrid, joins, without much enthusiasm, a battalion ruled by Commander Almendro, a tough veteran of the African war who soon notices a clear lack of military vocation in the new recruit.