Corporal Linda Maxwell worked for UNIT in the 1980s on attachment from Signals. In 1984, she tracked an extraterrestrial signal and investigated a fallen spacecraft. (AUDIO: The Helliax Rift)
In 1994, she worked with Gregory Lord thinking UNIT was the enemy due to her experiences in UNIT. She was influenced by Ship and wanted to release Daniel Hopkins. According to the UNIT files, she went missing 7 years previously, this was because she was abandoned by Hopkins' on a previous mission there. The Seventh Doctor asked her to cast the final vote to save the world. (AUDIO: Warlock's Cross)
Behind the scenes[]
The script for The Helliax Rift describes her as an "up-and-coming UNIT recruit. Had to fight to show her worth. Cool, collected with an edge."