The main character of the story, Harry, is incompatible with Mars and wants to return to Earth. He feels that the Martian climate will cloud his thinking and identity.

Harry's wife, Cora, tries to adjust to Mars and encourages her husband to accept life there.

The central theme of the story is change and adaptation. The Martian climate has changed people physically and mentally. It teaches students how environment and circumstances can change humans.

Harry's character represents the fear of the unknown. He wants to escape the climate and changes of Mars and return to Earth. This theme teaches students that facing unknown situations is natural, but must be faced.