Organon was an astrologer from Chloris.
Organon made predictions for the Lady Adrasta. One time, he predicted the arrival of a traveller from beyond the stars. As he was unable to elaborate on this, Adrasta was angered and had him thrown into the pit. Organon managed to survive and hid from Erato, a creature Adrasta kept in the pit.
Organon helped the Fourth Doctor reach safety after he was thrown into the pit. Together they began exploring the mine that lay about them. They came across Erato and the pair were separated. Erato captured the Doctor and Organon was trapped behind a barrier.
A party led by Adrasta came across Organon. The Doctor also joined them. Adrasta was prepared to have Organon seek out Erato despite his wishes. He was saved from doing so when Karela's scouting party returned.
After Adrasta was deposed and Erato freed, Organon devised a trading agreement between Chloris and Erato's homeworld, Tythonus. This allowed for the exchange of chlorophyll for metal. (TV: The Creature from the Pit)