After the souls leave Castiel, he apologizes to Dean, and pledges to find some way of redeeming himself. His plans are cut short when the Leviathans, who managed to hold on, take over his vessel. As the vessel rapidly deteriorates, the Leviathans march it into a reservoir, where it disappears beneath the water, releasing them.
Castiel is later founds hwandering wandering naked in the woods, with no memory of who he is, by [{Daphne Allen]] claims that God led her to him and takes him home. They later marryhe takes on the name Emmanuel Allen, and she supports his work as they marry. He discovers he has a healergift for healing.
While searching for a way to help Sam, whose psychosis is killing him, Dean searches for a healer called hears about Emmanuel - who turns out from another hunter, and is shocked to be discover it is Castiel. He Castiel eventually regains his memories, and is horrified at what he did. He tries to heal Sam, but unable to he chooses to take Sam's madness into his own mind.
==Characteristics==
Because he was an angel, Castiel initially expressed almost no emotion towards humans, and had little room for disobedience or feelings, as he was driven to follow his orders, although he does reveal some doubts about the morality of his orders.<ref name="four07">[[4.07 It's The Great Pumpkin, Sam Winchester]]</ref> As he spends more time with Dean, he develops empathy and affection for him, and eventually for those close to him, and humans in general. Castiel's superiors begin to question his loyalty and promote [[Uriel]] to oversee him. Castiel eventually rebels against and is ostracised from heaven. He allies himself with Dean, and despite his despondency over the absence of his maker and their desperate situation, Castiel continues to fight against the Apocalypse.
After his second resurrection by [[God]], with enhanced abilities, he sees his decisions and support of freewill to have been affirmed. Castiel begins to show pride, while remaining somewhat naive with regard to consequences. Crowley is able manipulate this budding sense of pride to get Castiel to start the Angelic Civil War. Castiel becomes dedicated to his own decisions, and tends to pass over other opinions, even Dean's, in the absence of another clear course. He eventually doublecrosses Crowley, taking in the souls of Purgatory alone. He then insists on worship from his former friends. He intends to be an involved god, a better and loving god who will not abandon the world. He renounces his dedication to free will, saying that angels need a firm hand. He is quick to smite those he feels to be hypocritical and unjust, and rewards those who have faith. But Castiel is being influenced by entities inside him (Leviathans), and his actions become erratic and violent. He realizes he is not strong enough to contain the power, and at a prompt from Sam, he goes to the brothers for help. He is apologetic and humbled; after the souls are out of him he wants to find a way to redeem himself before the brothers. The Leviathans end his plans.