Supernatural's return episode that will kick off the show's final run have arrived, and they're so on-brand it hurts.We don't know too much about the final season's return episode "Last Holiday," except the description teases that Sam (Jared Padalecki) and Dean (Jensen Ackles) discover a wood nymph (Meagan Fey) living in the bunker who is determined to protect her family, at any cost.