Meanwhile, isolated in her cell, Sister Gertrude sits in a catatonic state, detoxing from her drug abuse. As she regains mental clarity, she recalls the first murder committed in the hospital, of Sister Mathieu's grandfather. Gertrude realizes that it was in fact perpetrated by Sister Mathieu, as Gertrude watched in an intoxicated state. Gertrude, psychologically fragile and in a state of perpetual drug use, mistakenly assumed she was committing each of the murders, when it was in fact Sister Mathieu, motivated to kill by the sexual abuse she suffered as a child by her grandfather.