The five most popular story-specific questions about Death Valley, Series 1, Episode 6, excluding overall plot and ending, are:

1. What is the significance of the murder at the school reunion and how does it connect to the characters?
2. What shocking discovery from Janie's past is revealed in this episode?
3. How does John Chapel's unexpected news risk his friendship with Janie?
4. What role does Amber's brother Harrison play in the investigation?
5. How do the interactions and tensions among the reunion attendees contribute to the murder mystery?

These questions arise from the episode's focus on unraveling a murder at a 2010 school reunion, the cold case elements, and personal revelations affecting the main characters, as detailed in the episode summary and reviews.