Joseph Rubeish
Professor Joseph Rubeish was a scientist in the 20th century. He worked at a top secret research establishment focused on space hardware.
A renowned scientist, Rubeish was near-blind and had to wear powerful spectacles. When scientists began disappearing, he was confined by UNIT to the research facility for his safety, as were many other scientists. It was here that Rubeish became acquainted with the Third Doctor. He also met Sarah Jane Smith, who was masquerading as her aunt the virologist, Lavinia Smith.
Rubeish was transported to the Middle Ages by a Sontaran named Linx. He was almost hypnotised to work for Linx, but he was saved by his low vision. He found a microscope lens and heated it so he could see more clearly.
He saved Sarah's life from Linx's attack when he struck the probic vent on the back of Linx's neck, stunning Linx. Rubeish snapped the other scientists out of hypnosis and assisted in teleporting them back to the 20th century. He was the last to return to the 20th century. (TV: The Time Warrior)