Mary was a student at St. Cuthbert's and was the equivalent to the young Willow Rosenberg in being a shy and introverted student. Her parents being divorced, Mary visit her father Niles Weatherford, a scientist working in a museum, only the week-end. Noticing her rivality with the Queen B Meredith for Shane's heart interest, two other students Annabelle and Blythe proposes to help her against her nemesis. However, Mary, most frightened by Annabelle and her friends, refuses. In return, Annabelle and her friends harrassed her. In parallel, the Slayer Faith Lehane investigating vampiric murders on the campus, poses like a gym teacher. During a volley party, noticing that Meredith push expressly the ball on Mary's head, she convocate the two students in her office. Ironically, Mary find Meredith's body, savagely killed in the locker room. Suspecting Annabelle, she confront her into cafeteria under Faith and Winifred Burkle eye's, since decide to informate Shane. Ironically, this last is revelate to be an evoluated vampire, trapping here for Drusilla (working for Archaeus) who want to sired her for a mysterious reason. However, she was saved by Faith, Fred and Eldre Koh. Informating Faith on Drusilla's interest on her, she visit her father in his labo. Ironically, this last had find a mysterious demonic statut, supposed to be Drusilla's reason.