Detectives investigate the murder case of Walter in which there are no breakthroughs yet. They initially suspect David Hoshaw and find that he was at a Boy Scout week-long camp during the time of the murder, and later discover that Walter was over 200 miles away from the crime scene at the time of Walter's murder.
The detectives interview Walter, a former husband of one of the victims, but his alibi checks out. The investigation continues with the possibility of the killer being someone who had a key to the house.
A former prosecutor describes the emotional toll of working on cases where loved ones have been lost, and recounts a chance encounter with her ex-husband who had just been tracked down by the police.