When Carrie Martin's family falls on hard times, she struggles to support her frail sister and inadequate father. While scavenging along the shoreline of the Thames for firewood, she stumbles over the unconscious body of a young man. As she nurses him back to health she falls in love with the stranger. But there is a mystery surrounding the identity of "Mr. Jones" and, as Carrie tries to find out who he is, she finds herself in danger.