Buffy the Vampire Slayer - Season 7 Episode 13 The Killer in Me Get home before dark.
Overview: After Willow and Kennedy share their first kiss, Willow is transformed into Warren, the man she killed last year. When she sets out to find help, she bumps into an old friend. Meanwhile, Buffy searches for answers when Spike's chip causes him great pain, and the gang suspect that Giles may really be The First Evil.