Question: Walter O'Brien was played by which English actor?
Sentence (from "Elyes Gabel"): Among his most notable roles, he has portrayed Dr. Gupreet "Guppy" Sandhu in the "BBC" medical drama "Casualty", Dothraki Rakharo in Seasons 1 and 2 of the "HBO" series "Game of Thrones", and P.E. teacher Rob Cleaver in the BBC drama "Waterloo Road".
Relevant evidence: No