Debra Roberts

But it was Anthony's demeanor that really convinced Detective Weisbrot that his allegations might be the real deal.

Investigators decided to take a chance on Anthony's story because it was basically his word against Liam's.

They needed to prove that Anthony was telling the truth.

So they asked him if he was willing to go undercover.

With Anthony's help, police were hoping to record Liam implicating himself in Sarah's murder.

Over the next few days, they worked together to set up a meeting between Anthony and Liam.

Investigators said Anthony was driving back and forth between Brooklyn and Monmouth County.

He let detectives monitor and record any communication he had with Liam, any phone call, Snapchat picture, or message.

On January 31, 2017, investigators brought Anthony into the county prosecutor's office and asked him to call Liam on a recorded line.

Anthony was going to try to get Liam to talk about Sarah's murder.

It's been almost a month since the two friends have talked on the phone.

Anthony's voice is calm and controlled.

He even laughs at one of Liam's quips.

For a few minutes, it sounds like a normal conversation between friends.

But in reality, police are closely listening to every word.

And they have a plan.

The ruse is that Anthony needs money.

His camera broke, and he doesn't have the money to replace it.

Anthony's in a real bind.

So he asks Liam for help.