WHAT MUST SAM, DEAN AND CASTIEL SACRIFICE TO FOREVER SEAL HELL? — With Crowley (guest star Mark Sheppard) poised to undo all the good they’ve ever done as hunters, Sam and Dean find themselves cornered. But with Kevin’s (guest star Osric Chau) help, the Winchester brothers bound into one last play against The Demon King. Metatron (guest star Curtis Armstrong) initiates a plan with Castiel to take on Naomi (guest star Amanda Tapping) and the bureaucracy of Heaven. Alaina Huffman and Kim Rhodes also guest star. Phil Sgriccia directed the episode written by Jeremy Carver.