Calm, stoic captain Mac Whirr has just been given command of a new steamship, the Nan-Shan. He and his crew are transporting Asian workers across the China Sea when a sudden drop in atmospheric pressure alerts Mac Whirr of "some uncommonly dirty weather knocking about."

Soon the steamship, her crew, and the human cargo are caught in the midst of a vicious typhoon. The impending disaster brings out the best and the worst of Mac Whirr; Jukes, the chief mate; Solomon, the wise engineer; and the rest of the crew. Conrad shows that in the struggle for survival, true character will always be exposed.