New information causes Juliette to see her family's past differently—and she finally gains access to the silo's biggest secrets.

Racked with guilt, Billings sets off on a personal mission, only to discover a mind-blowing clue from Juliette.

Sims finds himself with a new position. Juliette learns Solo isn't being honest. Bernard and Lukas make an important discovery.

Bernard enacts a plan to root out Knox, Shirley, and Walker. Billings takes a stand. Solo saves Juliette's life and wants something in return.

Lukas is assigned a mission. Mechanical sends a powerful message. Juliette embarks on a perilous descent—and confronts a new danger.

Juliette discovers something's happened to Solo. Bernard makes an offer to Walker. Lukas meets with Salvador Quinn's descendants.

Billings' faith is shaken. Lukas heads to the down deep. Knox identifies the traitor. Juliette uncovers the truth about Solo's past.

The rebels make their move—and so does Juliette.