 Castiel is able to collect himself in time to return to the bunker and help Dean and the resurrected Mary Winchester find and rescue Sam.However, upon learning that Lucifer has escaped destruction, now jumping through vessels that rapidly burn out due to his weakened state making it harder for him to maintain them, Castiel sets out to find Lucifer, accompanied by Crowley, although their first attempt simply sees Rowena banish Lucifer's new vessel to the bottom of the ocean without actually managing to kill him.Lucifer eventually takes the President of the United States as his vessel, and conceives a child with one of the president's staff, but he is banished from this vessel thanks to the Winchesters and Crowley.