Blauensteiner was born on January 22, 1931 in Vienna. She was a compulsive gambler who spent her days in casinos, and she answered and placed advertisements in newspapers seeking companionship with elderly men.
Between 1981 and 1995 she killed her husband, two former lovers and two other men. Her method was Euglucon, a sulfonylurea prescribed for diabetes, which in a person who does not have the condition drives blood sugar down until they lose consciousness and die; she combined it with antidepressants and, in at least one case, left the victim in a cold room. The deaths were recorded as strokes and heart failure in elderly men. She inherited from them, was named in wills, and lost the money gambling.
She was arrested in 1996 after the family of one victim, Alois Pichler, questioned the will. She was convicted in 1997 of his murder and sentenced to life, and convicted again in 2001 in two further cases. The Austrian press called her the black widow.
Her lawyer, Harald Schmidt, was himself convicted in connection with the case, having been involved in the handling of a victim's estate. An outcome that made the case a scandal beyond the killings.
She died of a brain tumour in prison on November 18, 2003. Three murders were proved; the range of three to five or more reflects the deaths attributed and not charged.