Deborah Roberts

At this point, all the police really have is circumstantial evidence against Riley.

What they needed was the gun to conclude and prove that the bullet that left the barrel that entered Emma belonged to Riley's grandfather, which meant that Riley was the killer.

They wire up the two guys with microphones, a transmitter so they can listen in, and a video camera hidden in a key fob.

So you two now offer to help the police in a sting operation.

Were you worried about that?

It's now Tuesday, the day after Emma's body was discovered.

Alex and Noah invite Riley over to play video games.

Riley starts scheming ways that he can help his friends backpedal out of what they said.

What do you say to that?

So you're playing him at this point.

The Bluffs is out in the woods overlooking the Tennessee River.

They've all been there.

It's a place where teenagers go to hang out.

And just like that, the sting operation is on.

Now, Riley doesn't know, but three unmarked SUVs are tailing the boys.

We had told the boys that it was imperative that they actually physically see the handgun before they give us the signal to take him down.

Are you anxious, like you want to see it right away, or do you know that you've got to pace yourself?

What are you thinking?

Dang, is it in there?

Like, let me see.