Previously on Accused.

But I can't think he would just go into that furnace all by himself.

No one ever gave us any indication or reason to believe that foul play may have occurred.

A lot of people said, well, he jumped in there, he committed suicide.

No, no, he did not.

It was probably lowered into the furnace so he was probably murdered.

So I need to actually look into this person, what's this person's name?

I can take all the stuff off, I need to be able to...

Drop the camera.

Yeah, that's fine.

And the recording.

I'm Amber Hunt, and this is Accused, the mysterious death of David Bons.

Reporting any cold case is tough, but this one has presented some unique challenges.

For starters, everyone's sick, which has made setting up interviews difficult.

Harry Easterling was undergoing dialysis three times a week.

Mel Carnes brought a cardiac support dog to her interview.

Two unrelated people, one in employee, one in the widow of a former employee, had dementia.

It's not surprising, maybe, when you remember that David Bons disappeared 35 years ago,

and the people who worked alongside him were at least in their 30s back then,

not to mention, exposed for years to cancer-causing elements.

But the most unnerving moment involved a man whose father had been David Supervisor.

This man, named Charles Shao's after his dad, though the younger Shao's went by middle name Michael,

...