Frank ordered the FBI to obtain access to LabCorp's records. Cross-referencing who had access to each blood sample, the hundreds of employees were narrowed down to a dozen suspects.

Rather than be interviewed, Frank had them monitored at work. Hidden cameras placed in every office, hallway and bathroom they used.

Frank:
-access to a blood lab is extremely useful for acquiring genetic samples
-if it's still being used this is the chance to catch the kid

And sure enough, Mrs. Miller revealed herself to be stealing drops of blood when alone.

Cameras were placed in her house and vehicle. Her calls intercepted. Internet use logged. Google/Facebook/Amazon accounts backdoored under warrant. Teams of agents tailed her 24/7.

-we're looking for any movement of the blood samples
-and anything that might be a signal to the kid

[Friday Night]

Beth-ann is in her bed, browsing instagram posts on her phone.
Mr. and Mrs. Miller lay in bed watching Colbert together.
Beth-ann and Mr. Miller simultaneously fall asleep.

-it's happening

Mrs. Miller exits her bed and picks up a notepad and pen.
Mr. Miller speaks in his sleep...

Davidson Park. South entrance. Third bench on the left side. Packed on left side. Fourth slot.

Mrs. Miller writes. Rips off the page. Folds it. Places it in her purse, where the blood samples were last seen placed.

-sounds like instructions for a dead drop

Mrs. Miller gets dressed. Picks up her purse. Exits the room. Exits the house. Gets in her car.

Agents follow Mrs. Miller to Davidson Park.

Mrs. Miller exits her car. Pulls out a paper from her purse. Unfolds and read it. Rips it up. Tosses it in a trashcan.
Mrs. Miller walks through the park. Stops at the third bench on the left side of the path. Sits on the left side of bench.
Mrs. Miller takes out a folded piece of paper from her purse and carefully stuffs it inside a slot in the bench.

Agents witness and report all of this from their car.

Mrs. Miller leaves the park. Returns to her car. Returns home. Undresses. Gets in bed.

Twenty minutes later, Beth-ann and Mr. Miller simultaneously wake up.

-now we just need to wait for the pickup