Poul was a renowned ship builder, having amassed a considerable estate in addition to multiple awards and commendations.
Due to the nature of his work, Poul was away from his family for extended periods of time, the only break in this being when Poul was reassigned to Earth during Isaac's first four years of life. Upon completion of this tour, Poul went on an extended off-world tour during which he seemingly vanished. His service record was considered highly classified and Isaac's continuous attempts to locate him were rebuffed.
Unknown to Isaac, the government had files on his father classified as "Top Secret".
- Like his wife and son, the name Poul Clarke references two revered science fiction writers: Poul Anderson and Arthur C. Clarke.