Javaman

The  was a scientist.

The Javaman was responsible for an insurrection on Wermir Colony A. He was wanted by the Space Security Service and was under a death sentence that had been signed by Mavic Chen. He had won the Dastari prize for two consecutive years because of his "considerable imagination as a scientist".

He invented a machine that he called the Dorganator. It emitted theta-waves, allowing him to project his thoughts into others. The Dorganator was located in a cave on the planet Volnex VI, and the Javaman used it to control the native Volnexians.

Wanting to discover the secrets of time travel, the Javaman used the Dorganator to draw the TARDIS to Volnex. However, the theta-waves had an effect he didn't expect - it switched the Sixth Doctor and Peri's minds into each other's bodies, a process known as corporelectroscopy. The Javaman had the Volnexians capture the Doctor (with Peri's mind in his body), and tried to force "him" to tell the secrets of time travel. The Doctor, in Peri's body, sabotaged the Dorganator, causing the cave to collapse with the Javaman still inside. (PROSE: Turnabout is Fair Play)