Diana Duve was 26 when she vanished one night in 2014 in Vero Beach, Fla. She was last seen alive leaving a bar with her on-again, off-again boyfriend, Michael Jones. To witnesses, the couple seemed to be having a good time, though they told police that at one point it looked like Duve was upset. She never returned home. Her mother knew something was wrong when her daughter didn't call her, something she did every day. Contributor Michelle Miller and 48 HOURS report on what happened that night.

Donna Ongsiako was home alone in her Colts Neck, N.J., home after midnight when she heard a noise downstairs near the door. She thought that she forgot to let the cat back in. When she opened the door, her life changed forever. There was a young man with a knife, who pushed his way in and began to repeatedly stab her. Ongsiako talks with contributor Jim Axelrod about her inspirational story of survival and her efforts to help other victims of random violence.