John Sharon

, like his father and four older brothers, was part of Global Response. As part of the team, he manned Lightning 5, their communications satellite.

After the end of the organisation, he became a physician. He went to a rainforest to help a tribe contaminated by an attack by the Myloki. He told the Second Doctor that Grant Matthews was likely still on Sharon Island, where he had sought refuge years before. (PROSE: The Indestructible Man)