She Knew the Man in the House: The Tapp Murders

In 1984, Margaret Tapp and her nine-year-old daughter, Seana, were found strangled inside their Ferntree Gully home. More than four decades later, their murders remain unsolved, but this case was not lacking suspects or physical evidence.

Allison and Sophia revisit the disturbing investigative failures surrounding the case, including a retired police officer who was allowed to enter the crime scene and remove a book, evidence that later disappeared, a crucial DNA sample that was cross-contaminated, and questions about how a suspect could be cleared when seemingly little remained for comparison.

After visiting the family’s home and gravesite in Australia, Allison also shares new impressions she received about the final moments of Margaret and Seana’s lives—and why she believes the positioning of Margaret’s hands may reveal something chilling about the killer.