Dahh-Ren

Dahh-Ren was an individual from an unknown planet, as well as the only non-human survivor at Chasm Forge. He disliked being called "Darren" and accused Bill Potts of being racist. (TV: Oxygen)

Behind the scenes

 * Sources differ as to whether Dahh-Ren is human or alien. The official Doctor Who website describes him as a "non-human". . Actor Peter Caulfield says he is a human who is "genetically different".