Celia Coulson begins an uncertain passage when the ship taking her and her teenage daughter to England passes beneath Australia's Sydney Harbour Bridge. It's a passage that becomes complicated by a mysterious stranger and the outbreak of war in Europe. The stranger guides them through dangers that occur during the journey, but suspicions arise about his intentions. His response to the suspicions is simply: "Things are not always what they appear to be." In the end, Celia realizes that while no passage is ever trouble free, there are passages that must be taken.