Sam (Jared Padalecki) and Dean (Jensen Ackles) spend their lives on the road, battling every kind of otherworldly threat. Over the years, in dozens of bloody adventures, they face everything from the yellow-eyed demon that killed their mother to vampires, ghosts, shapeshifters, angels and fallen gods. They even come face to face with Lucifer and God themselves. With the help of allies both human and nonhuman--including the fallen angel Castiel (Misha Collins)--they discover that every threat they vanquish opens a new door for evil to enter. As dawn arrives, after endless struggle and sacrifice to defeat the world's evils, they know that, come nightfall, something otherworldly--something supernatural--will claw its way from the shadows, demanding their attention.