George Litefoot
George Litefoot was a pathologist in London in the 1880s whose path intersected with the Doctor more than once.
Profile
Litefoot assisted the Doctor in investigating Magnus Greel and became good friends with Henry Gordon Jago. (DW: The Talons of Weng-Chiang) Jago and Litefoot later descended into the London sewers to kill the rest of Greel's remaining giant rats with a Gatling gun and on the way there, failed to recognize the Doctor, who had regenerated (DWM: A Victorian Interlude).
His association with Henry Gordon Jago is known to have continued beyond their adventure with the Doctor. The pair were involved as amateur sleuths in at least one other mystery. (BFA: The Mahogany Murderers)
In 1894 he again assisted the Doctor and his companion Samantha Jones in investigating a Zygon ship beneath the Thames. (EDA: The Bodysnatchers)