Buffy the Vampire Slayer Season 7 Episode 4 : Help

Buffy is settling in to her counselor's role at the high school helping troubled teens and sorting out problems, but is left speechless when Cassie, a student, comes to her and calmly tells her that she (Cassie) has only a week to live. Suspecting the girl is suicidal, Buffy investigates and discovers a cult of students playing with dark forces and comes to believe Cassie is psychic.