Dr. Troughton was a human settler on Gilead who later became a personal physician to First Citizen Lattus Tishla. He discovered the infection killing her unborn twins was mersa and began looking for sources outside the Compact and the Realm for nanobiotics that would kill the infection. He traveled to the Laputan Guardianship to obtain the nanobiotics. Upon his return, he was able to save Lattus Athena. However, Lattus Kai-ban had died at birth as the infection had overwhelemed him.

Dr. Troughton is named for Patrick Troughton, who played the Second Doctor on Doctor Who.

Appearances: Tishla