Yana
Professor Yana was a human scientist, who was in reality a fifth (on-screen) incarnation of the renegade Time Lord known as the Master. The Master transformed himself into Yana through the Chameleon Arch.
- Details concerning Yana's early life are the false memories of the Yana persona, likely fabricated by the Master's TARDIS.
Yana was an orphan found on the coast of the Silver Devastation with only a fob watch, which in reality held the Time Lord self of the Master. He could never keep time and was always late for things. He spent his life moving from one refugee ship to another and all his life he heard the sound of drums every waking hour as if they were getting closer.
He eventually became friends with the scientist Chantho, a Malmooth who was thought to be the last of her kind. Together, they worked on the Utopia Project to get the humans on Malcassairo to the planet Utopia.
Eventually, when he met the Doctor and Martha Jones, he thought more about the watch because of their talk, saying things like "Time Vortex", "Time War", and "regeneration", which clicked in his mind and he heard the voice of the Master within. He finally opened the watch and became the Master.
As the Master, he let the Futurekind into the base to try and kill the Doctor and suceeded in killing Chantho, but before she died, she shot him and forced his regeneration into the Sixth Master.
His killing of Chantho meant he was responsible for the extinction of the Malmooth.
(DW: Utopia)
Yana's name was an acronym for the Face of Boe's last words: You are not alone." How the connection was made is unknown. Possibly
the doing of Jack Harkness/TheFace of Boe.