Written at the start of the Great War, when his son Borys was at the Western Front, The Shadow-Line is Conrad's supreme effort to open man's eyes to the meaning of war through the stimulus of art. In many ways an autobiographical narrative, this masterpiece relates the story of a young and inexperienced sea captain whose first command finds him with a ship becalmed in tropical seas and a crew smitten with fever. As he wrestles with his conscience and with the sense of isolation that his position imposes, the captain crosses the "shadow-line" between youth and adulthood.

It is the qualities needed to confront the ship's crisis that symbolize the qualities needed by humanity, not only to face evil and destruction but also to come to terms with life.