Zennox

 was an archaeologist visiting a planet which had a Cyberman citadel. The Sixth Doctor was cautious of her. She wanted to take the Cyber-Planner from the planet and put it in a museum and reactivate it. She wanted to install Findel as the Cyber-Planner but instead decided to use Zoe Heriot instead.

When she used the beacon to summon the last of the Cybermen, the Cybermen arrived at the citadel and killed Zennox. (AUDIO: Last of the Cyberman)