Let's say a character comes across something that Was Once a Man and, after discovering the source of The Virus that made it that way, looks in the mirror to find that he shows all the signs of being infected with it. Cue "Oh Crap." Roll credits. Either way, we know he's screwed. And unless he can Find the Cure, fight off his fate or have some miraculous Deus Ex Machina save him, all he can do is sit back and wait to die. In most cases, he's not going to find the cure or get rescued. (Except maybe in Fanfic. By aliens.) Since this is a form of foreshadowing and an Ending Trope, spoilers abound.