Jeremy (Interference)

Jeremy was a government worker with connections to the Home Office. Sarah Jane Smith contacted him for information in 1996 while he was at the Prince Leslie. (PROSE: Interference - Book Two)

Behind the scenes
It is implied that Jeremy was Jeremy Fitzoliver, who was a colleague of Sarah Jane Smith. (PROSE: Island of Death, AUDIO: The Paradise of Death) However, if he was also John Doe, then that would be impossible, as he was killed in 1993. (PROSE: Instruments of Darkness)