Sam is near death following the trials to close the gates of Hell so a desperate Dean tricks Sam into consenting to be possessed by the angel Ezekiel. But this angel is not Ezekiel after all. He is Gadreel, an infamous angel who had been imprisoned in Heaven's jail. Dean meets Cain, the father of murder. Dean receives the Mark of Cain. Season 9 ends with a dramatic cliffhanger. The Road So Far: Supernatural episode poems, Vol. 8 is a complete collection of all of the Season 9 episodes set to poetry.