Following the defeat and imprisonment of Metatron, Heaven is reopened to the angels and most return home without a fight. However, some refuse including Daniel and Adina who kill an angel sent to retrieve them. In order to get the two rogue angels back, Hannah recruits Castiel whose stolen grace is diminishing, causing him to grow ever weaker and closer to death as time goes by. The two are able to locate Daniel at his campsite, but he refuses to return and convinces Castiel and Hannah to sit peacefully with him for a while as he attempts to sway the two angels, particularly Castiel, to his view of the world.
As the three talk, Adina arrives armed with an angel blade that she refuses to put away until Hannah puts her own away. While Daniel and Castiel try to defuse the situation, Adina believes that they will never be free and engages in a fight with Hannah, slicing open her shoulder and knocking her to the ground. Before Adina can stab her, Hannah hits her in the face with a rock, stunning Adina and knocking her to the ground. Desperate to protect Adina, Daniel goes after the wounded Hannah, forcing Castiel to join the fight and kill Daniel from behind with his own angel blade. Enraged by Daniel's death, Adina attacks Castiel, slicing him across the chest before running away. Though Hannah wants to go after Adina, Castiel recognizes the futility of the attempt and Adina gets away.
At Sam Winchester's request, Castiel and Hannah make their way towards the Men of Letters bunker to aid Sam in curing Dean of being a demon. Unknown to them, they are followed by a vengeful Adina who murders a clerk at a gas station about five miles from the bunker where Castiel and Hannah stop for gas and lies in wait to ambush them.
Entering the gas station, Hannah finds the dead clerk and is taken hostage by Adina who holds an angel blade to her throat as Castiel enters. Adina tells Castiel that he will pay for killing Daniel and Castiel draws his own angel blade. However, Castiel's grace is nearly burnt out and drawing his angel blade leaves him dizzy. Adina throws Hannah into some shelves, breaking them and stunning Hannah. Adina attacks Castiel who is no match for her in his weakened state and she easily disarms him. Castiel pleads for Adina to just kill him and let Hannah go, but Adina tells them that she plans to kill Castiel very slowly and make Hannah watch. Adina then kicks Castiel through a glass door into the parking lot where she beats him into a bloody pulp.
After beating Castiel, Adina returns her attention to Hannah and begins torturing her with an angel blade to make Hannah suffer for Daniel's death. Hannah tells Adina that Daniel's death is on Adina's head, not hers and the two had murdered an angel and they had to pay for it. Adina feels that she and Daniel were justified in killing the angel as the angel would've forced them to go back to Heaven and insists that the angels should've just left her and Daniel alone.
Before Adina can cause Hannah any further harm, Crowley interrupts. Adina rises to face Crowley who quickly slices her throat open with an angel blade of his own and draws Adina's grace into a small vial, turning Adina human. Crowley then stabs Adina through the chest with his angel blade, killing her.
With Adina dead, Crowley heads to Castiel's side to give him Adina's grace. Though Castiel refuses at first, Crowley tells him that Castiel's hands are clean as Adina was killing Hannah and Crowley needs him alive. Castiel reluctantly accepts Adina's grace from Crowley, restoring his powers and health and instantly healing his injuries from Adina's attack. Crowley explains that he helped Castiel as demon Dean has become a problem for him and he needs Castiel to help Sam clean up the mess. Crowley then departs, leaving Castiel and the still-injured Hannah to continue on.
Following the fight, Castiel and Hannah continue on to the Men of Letters bunker where Castiel arrives in time to help restrain Dean and finish the cure. With Adina's grace, Castiel is restored to full health and eventually regains his full power when he later gets the remnants of his own grace back.
After helping Dean, Castiel and Hannah continue their mission to return the rogue angels to Heaven and eventually get most of them to go back without a fight by the time Hannah chooses to return herself.
- This is one of the only times Crowley kills an angel with the other being Esper with a special gun loaded with Angel-killing bullets.
- Taking Adina's grace puts Castiel in the same position he was in after stealing Theo's until Book of the Damned when he regained the remnants of his own grace.