John Jefferson

John Maynard Jefferson was the head of security for the Walker Expedition. The Beast noted him to be haunted by "the eyes of his wife". When the Ood were possessed by the Beast, Jefferson sacrificed his life to save Rose Tyler and what remained of his team. As a last request, he asked Zachary Cross Flane to pull the oxygen out of the air duct he was in, as he chose to suffocate, rather than be killed by Ood. (DW: The Impossible Planet / The Satan Pit)