David is contacted by Anne Gibbs, an alien who is on the run from both her fellow aliens and humans. She is the undesired result of an attempt to mimic human behavior by creating emotion. It's been successful in part, as she now values her own life as well as those of humans, but in the process she frequently now loses control and becomes violent when even mildly angered, and has killed a woman in one of her outbursts. Still, she tells David she will come with him to Washington to tell officials everything she knows about the aliens' plans. But the aliens plan to kill her to stop her, and the husband of the woman she killed is also after her seeking revenge.