SUPERNATURAL Season 10 Episode 20 : Angel Heart

When Claire Novak gets a lead on her mother, Amelia, who has been missing for years, Castiel asks Sam and Dean to help her. Castiel feels guilty for what he did to the Novak family and wants to make amends by reuniting Claire with her mom. However, when they find out what took Amelia, they realize there is a chance Claire may not get her happy ending.