Hayton

 was a scientist who was experimented using the hallucinogens produced by the Kyropites. He was interested in the Fifth Doctor when he was brought to him. He showed the Doctor one of the Jekylls. He worked out that the Jekylls and Kyropites worked in symbiosis. He said that the dreams that the Kyropites that the dream's effects from the victims' fantasies. He wanted to sell it on the open market. (AUDIO: The Mind's Eye)