I'm looking for a fic that explains why Giles tried to kill Spike in Season 7 - at the end of 'Sleeper' (Ep 7x8), Giles was either replaced or infected by the First/Bringers. I think the fic starts post Season 7. Buffy/the Scoobies are able to cleanse/cure Giles later. That's all I remember about the fic!