When jewelry seller Minerva Cantu, 26, is found bound, gagged and lifeless in her home, police suspect robbery as the motive. But who killed this mother as her infant slept in the next room is a mystery that would haunt one detective for 20 years.

When Mary Scott, 23, is found murdered in her San Diego home in 1969, a case with few leads quickly loses steam. Years later, Mary's daughters grow determined to find answers about the mother they barely knew, and a crime that's 50 years cold.