When Joe Valery comes back to Kate’s office and finds her dead, he searches her desk for valuables. He finds the envelope full of incriminating pictures of the important men of Salinas and pockets them, believing he has struck gold. Just then the sheriff arrives and asks for Joe to come down to the station. Joe agrees, but when they get outside he makes a run for it, and is shot dead. The sheriff finds the photos in his pocket and resolves to destroy them. The next day the sheriff goes to see Adam Trask and informs him that his wife has killed herself, and left her fortune to Aron. It becomes clear to Adam that he must tell his son about Catherine.
Catherine does succeed in destroying Joe ultimately. Her death also finally prompts Adam to realize that he cannot protect his son from the truth any longer, but the bitter irony here is that Adam has had this realization too late—his son Cal has already told Aron the truth. Cal has essentially done Catherine’s job for her—this highlights the extent to which his revealing her identity to his brother was an evil thing to do.
Adam and Lee wait for Aron to come home. When they don’t see him for a while they ask Cal if he knows where he brother is. Cal says “am I supposed to look after him?” But when Cal leaves he drinks himself into a stupor from guilt—he is worried something horrible has happened to Aron. He goes home and finds the gold certificates in his desk, and burns them up one by one.
This is a near perfect reenactment of Cain’s famous line in the Bible’s book of Genesis: “Am I my brother’s keeper?” The reality is that Cal was, in fact, his brother’s keeper—and he failed to protect him from the truth. Cal burns up the gift that caused him to destroy his brother, symbolically rejecting the evil side of himself.
Lee finds Cal, and tells him that his mother committed suicide. Lee explains softly that people, especially Americans, who are spectacularly excessive, who throw their weight around with so much passion, are violent. He explains everyone is descended of barbarism. Lee leaves when he sees Cal understand, and finds Adam in the hall, slumped against the wall clutching a note in his hands. It is from Aron, and it reads “Dear Father, I’m in the army…don’t worry about me. Aron.”
Lee explains to Cal that everyone is violent, everyone is destructive—it is in our blood, so to speak. This helps Cal contextualize his own actions—he is an extension of a long history of humanity, and humanity is both evil and virtuous. Aron’s fate is finally made clear, however, and now Cal, like Cain, must contend with his wrongdoing.