L. D. Ia was a biologist whose mind was stolen by Skagra on the Think Tank space station. He died in the destruction of the station. (HOMEVID: Shada)
However, Ia's mind lived on in the Sphere. After the Fourth Doctor defeated Skagra, he took the Sphere to Drornid, where he had the minds of Ia and the other victims of the Sphere transplanted into new bodies. (PROSE: Shada)
Behind the scenes
The names of Santori and the other Think Tank scientists are all derived from locations or geographical features associated with the volcanic Greek island Santorini. Ia is derived from the village of Oia.