Adrasta

Lady Adrasta was the ruler of Chloris, a lush jungle world where metal in all forms was a rare and prized commodity.

Biography
Adrasta gained power by holding the monopoly of the planet's metal. All of this metal came from the planet's only mine, the entrance to which was a pit that was guarded fiercely by Adrasta's men. She was aided by Karela and the Huntsman, the latter of which controlled Adrasta's Wolfweeds. These Wolfweeds had been grown for her use in nurseries within the palace.

When Erato, an ambassador from Tythonus, which had a lack of chlorophyll but an abundance of metal, attempted to start trade negotiations, she had him thrown into the pit rather than lose her monopoly. Anyone who opposed or failed her was thrown into the pit to be eaten by the creature. She kept the origins of the creature a secret from her people.

Fifteen years later, when the Fourth Doctor came to Chloris, Adrasta was interested as to what he made of Erato's craft. She was interested in his theory that it was an egg. However, the Doctor threw himself into the pit and so Adrasta took Romana prisoner instead, hoping she knew something about the object. She also had K9 brought to her palace as he was made of valuable metal.

From K9's data banks, Adrasta learnt about the TARDIS. She saw its powers as a way to dominate the planet without need for the creature to protect her mine. She decided to have K9 kill the creature and so took a party into the mine.

As they advanced towards the creature, it created a protective barrier to prevent their approach. Adrasta had K9 attack it but this proved fruitless. The Doctor was able to break through from the other side and she took him as a prisoner.

Erato approached the party while Adrasta was unprepared. She cowered in fear and attempted to flee, but the Doctor held her. Erato was able to talk through the Tythonian Communicator which had to be touched by someone else. Realising her deceit, the Huntsman used the Wolfweeds to force Adrasta into using the communicator. She did so and Erato told all present how she had acted selfishly rather than for the good of her planet. In revenge Erato attacked her, as did the Wolfweeds. She was killed in a manner of seconds with her body dissolved. (DW: The Creature from the Pit)

Behind the scenes

 * In David Fisher's original script, Lady Adrasta was Queen Adastra, whose name meant "to the stars" in Latin. This was changed by Douglas Adams.