Sir Keith Gold was the executive director of the Inferno Project. However, he was only a figurehead due to Professor Stahlman's favor with the ministry. He had little to no authority to do anything but advise Stahlman. However, concerned about Stahlman's recklessness, he brought on a variety of different experts to advise Stahlman, much to the Professor's annoyance. He was the one who brought UNIT in on the project, particular the Doctor, and later drilling expert Greg Sutton. None of them seemed to do any good, and Stahlman insisted on ignoring them and pressing ahead without regard for proper safety procedures. Eventually, fed up with Stahlman browbeating him, he went to London to speak to the minister who'd given the go-ahead for the project, to express his concerns about Stahlman.
Stahlman, realizing what Sir Keith intended to do, paid off his chauffeur Patterson to drive Sir Keith out into the middle of nowhere in the event that the minister sided with Sir Keith against him. When the minister heeded Sir Keith's warnings, Patterson did as he'd been instructed and didn't drive his employer immediately back to the Project Inferno compound, instead taking him out of the way to prevent his getting back before penetration zero. Although Sir Keith was able to threaten Patterson into obeying him and taking him back so he could stop Stahlman, the two were involved in a car accident which left Sir Keith with a broken arm. Despite this, he still managed to get back before the drill reached penetration zero.
Even with the authority of the ministry behind him, Sir Keith still couldn't get Stahlman, by this time turning into a Primord to stop the drill. However, once Stahlman completed his transformation and turned into a savage beast, Sir Keith was finally able to overrule him. After the Doctor subdued Stahlman, Sir Keith gave the order to shut down the drill, bringing Inferno to a halt.
In the alternate universe, Sir Keith Gold died in the car crash.