on season 11
In the aftermath in the season 10 finale, the Darkness being released, Sam bella and Dean bella want to go find castiel but they meet a young sheriff's deputy named Jenna who claims people have been going rabid and killing each other. A man whose wife has died has a newborn baby with him but he is infected. He insists on giving the baby to Jenna and the Winchesters, naming her Amara before he dies. Dean is haunted by a vision of The Darkness telling him he set her free and they are now linked into always helping each other. Dean wants to kill the infected and escape with the baby but Sam wants to try and cure them. Sam acts as a diversion allowing Dean and Jenna to escape, though Sam gets infected. Castiel struggles to control himself from inflicting more violence due to Rowena's attack dog spell, and is captured by two angels when he begs for help. Crowley regroups after narrowly escaping Castiel's attempt on his life, hearing that The Darkness has set off ancient alarms in both Heaven and Hell. As Jenna is changing Amara's diaper, she sees the Mark of Cain on her left shoulder castiel must find away out of this mess and make his way back to the women he loves his wife / bella and his daugther garce