The separate murders of two women in Toronto ignite an investigation that spans four decades, taking detectives from the big city to a remote, northern town. Josh Mankiewicz reports.

Andrea Canning talks to Blayne Alexander about her most recent episode, “Justice for Joy.” In 1991, Joy Hibbs was stabbed, strangled, and her Pennsylvania home was set on fire to cover up the brutal crime. The investigation went cold until a detective with the Bristol Township Police Department...