Victor Chaplin was Jenny Chaplin's brother. (AUDIO: After the Daleks) He was taken by the Daleks to become a Roboman (TV: The Dalek Invasion of Earth) in 2166. (PROSE: Lucifer Rising)
After the Daleks' conquest had ended, Jenny found her brother. Victor was discovered in Hyde Park, with other converted Robomen. He did not remember his original identity and still thought himself a servant to his masters, the Daleks. Jenny brought Susan Foreman to visit him, and he revealed that one Dalek still remained on Earth. (AUDIO: After the Daleks)