It's estimated that there are 25 to 50 active serial killers in the United States at this very moment.

And I want you to think about that lone stranger who you passed by in the grocery store the

other day, or that neighbor you waved good morning to. What about the person standing in front of

you in line grabbing a coffee? Could one of them be a serial killer yet to be caught?

How would you know if you were staring into the face of evil? The fact is, most of us wouldn't have a

clue. And chances are, you unknowingly walked past a serial killer at some point in your life

and had no idea. For residents of Long Island, the odds of unknowingly passing by a serial

killer have been much higher in recent years, as there's been a monster living among them. He's known

as the Long Island serial killer. Residents have lived in fear. In their minds, they knew this

murderer could be anyone. Since the first bodies were discovered in 2010, the investigation came in waves, but eventually

seemed to go cold as whoever this killer was, when inactive.

Where did this twisted monster go?

Was he still out there?

Profilers studied the case files up and down and concluded that this

serial killer was likely a white male, middle age, educated, financially stable, and possibly married,

and they were right. This past week, a suspect in the killings has been brought into custody.

His name is Rex Heuerman, a 59-year-old architect who lived in Massapequa Park on Long Island.

This monster was living under investigators' noses the entire time.

He was a local businessman, a suburban dad.

He's married and a father of two. This infamous series of unsolved murders

has haunted Long Island for over a decade, and will go down as one of the most prolific

searches for a serial killer in recent history. But how did all of this happen? I'm Avery Ross,

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