Three waifs--a boy, a girl, and a child--live aboard a steam dredge owned by a cruel dredge master. Unable to tolerate the waterfront conditions and the dredge master's foul attentions toward the girl, the three flee to the city where a white slaver attempts to make the girl a prostitute. The white slaver himself makes advances toward the girl, and the boy finds the courage to defend her. The three then go off in search of a better life together.