Marian Schaeffer

 was a scientist who worked on the planet Burnt Salt in the year 2284. She was attempting to research a cure to cyber-smoke.

She was married to the famed naturalist and zoologist Bernard Schaeffer. Unlike her husband, she was originally a surgeon but became a scientist to research an antidote to cyber-smoke.

Professor Schaeffer was responsible for the Cybermen arriving on Burnt Salt in 2284 and originally seemed to be intent on making a deal with the them much to the Doctor's chagrin, however, she later revealed her true motivation was to destroy the Cybermen after what they had done to her husband Bernard.

She lived in the Bernard Schaeffer Project complex. She bred the Lamuri found on Burnt Salt, including Skippa. (AUDIO: The Tyrants of Logic)