Coetzee

Coetzee was the leader of a colony that had lived on an asteroid of gold for twenty-five years, where they had been forced to skin the reptilian inhabitants for clothing and wear eye protection against the sun. When Kellman arrived on the asteroid from the Nerva Beacon, Coetzee sent her son, Joseph, to act as a vanguard as Kellman negotiated a treaty with the Nerva for the colony. However, the Fourth Doctor eventually arrived to expose Kellman as a liar, revealing that he had killed Joseph to keep the colony a secret from the Nerva so he could steal the gold for himself, producing a locket he had taken from Joseph's body as proof of his claim.

As Kellman made his escape from the colony, he managed to ambush Coetzee and fatally injury her, but she managed to set off a rock slide that killed Kellman before she died. Her dying request was for the Doctor to get her colony to the Nerva Beacon. (AUDIO: Return of the Cybermen)