Welcome to 48 hours post-mortem. I'm CBS News correspondent and Marie Green, and today we are talking about an episode that truly sent shivers down my spine, unmasking the zombie hunter.

So joining me now are 48 hours correspondent Peter Vancent and producer Paula Rosa, who reported on and produced this episode.

Welcome, gentlemen.

Hi, thanks for having us.

Hey, Ann Marie. Happy Halloween.

It's a perfect episode for Halloween.

It says it in the name, right?

The Zombie Hunter.

But before we get into the episode, let's play a clip from the show.

There are not many crimes that are like this one.

You had women riding bicycles along the canal on a typical Phoenix evening, ambushed,

stabbed multiple times. Brianna Whitney, the true crime reporter for the CBS affiliate KPHO in Phoenix,

says the first victim was 21-year-old Angela Brasso, whose body was found in November

1992. Police are looking at this scene and thinking, what on earth happened and who did this?

Ten months later, the body of 17-year-old Melanie Bernice was found in one of the city's canals.

Investigators found the same DNA at both scenes, says Detective Clark Schwartzcoff.

I think there was over 600 persons of interest.

After some 20 years, investigators zeroed in on 42-year-old Brian Patrick Miller, a divorced father raising his teenage daughter.

As Schwartzcoff soon learned, Miller had a unique alter ego.

Everybody in the Phoenix area knew Brian Patrick Miller as this character called the zombie hunter.

Schwarzkopf secured Miller's DNA. Days later, the head of the forensic lab had some news.

She leans down to me, she goes, it's him. I go, what? She goes, Brian Miller. It's him.

...