Dr. Temperance Brennan (aka Bones) is pregnant. As the pregnancy progresses, it becomes obvious to everyone that it's not a human fetus. She is being guarded by a centipede/alien-like creature that prevents anyone from "saving" her although it's likely too late even if someone could. Her body is contorting and the birth will no doubt be deadly and it's likely her body will be the offspring's first meal. Angela arrives and gives her a cigarette. Bones puts the lit cigarette backwards (lit end) into her mouth. It's the best way to die at this point.