Ava takes her first steps toward understanding the halo's power, but a baptism by fire at the hands of the Order leaves her feeling burned.

As Ava contemplates starting over, she recalls being left to the tender mercies of the orphanage. The Sister Warriors suit up for a dangerous mission.

While Mary squares off with Sister Lilith, Ava begins to open up to JC, and Jillian Salvius fires a warning shot at the Church.

Ava experiences a come-to-Jesus moment courtesy of Mary, who pulls no punches as she shows her just how many souls have their own cross to bear.

Hoping to find some answers, Ava puts her faith in science. Meanwhile, Cardinal Duretti's machinations sow seeds of dissension inside the Order.

Secrets are revealed and a Sister Warrior mysteriously returns to the fold as Ava and her allies attempt to keep a sacred object out of the wrong hands.

"The weapons we fight with are not the weapons of the world. On the contrary, they have divine power to demolish strongholds. " Infiltrating the Vatican to find a tomb hidden deep underground for a millennium? Hell, Ava may need a miracle to pull off this mission.

"Do not be afraid of what you are about to suffer. I tell you, the devil will put some of you in prison to test you, and you will suffer persecution for ten days. Be faithful, even to the point of death, and I will give you life as your victor's crown." In shock over the contents of the tomb, Ava no longer knows what — or who — to believe as she tries to divine the true history of the halo.