Thomas Perry's Nightlife follows a female chameleon (and serial killer) as she repeatedly reinvents herself in order to avoid capture. As the story opens, the beautiful Tanya Sterling has just carefully killed her latest suitor and slipped out of his apartment unnoticed. Her seemingly innocuous computer geek boyfriend, however, happens to be the cousin of a dangerous Los Angeles thug named Hugo Poole. Worried that his cousin's death might be some sort of "message" from unknown parties, Poole hires a private detective named Joe Pitt to investigate.

Pitt — a former prosecutorial investigator — travels to Oregon to investigate the death. His involvement in the official police investigation is assured, both by his sterling reputation and by Poole's own requests. This does not sit well with Portland homicide detective Catherine Hobbes, who must nonetheless incorporate the Tinseltown detective into her search for the killer. Hobbes and Pitt form an uncomfortable alliance of convenience as they conduct their parallel investigations; it doesn't help that the tension between them also tosses off a few romantic sparks.

What seems as if it might be a hunt for an elusive witness soon becomes something more as Hobbes and Pitt track the mysterious "Tanya Sterling" from Portland, only to run into a new identity: Rachel Sturbridge. With the heat on, Rachel quickly becomes Nancy Mills, and so on. "Tanya" is an apparent expert at forging documents and changing her appearance almost on a whim. She is able to take swift advantage of the system and institutions around her, but as the net closes around her she finds herself resorting more and more to violence. Hobbes soon becomes convinced that the woman she once thought was a reluctant witness to her boyfriend's murder is actually an efficient killer in her own right.

Hobbes tracks Tanya from Portland to San Francisco and beyond. She always seems one step behind Tanya, who has quickly become accustomed to leaving dead bodies in her wake. In Tanya, who is in reality a young woman named Charlene, Perry has created an intriguing villain. She is in certain respects the extreme extension of contemporary consumer culture, a caricature of someone who has truly embraced the idea that she can — and should — have it all. Perry suggests that Tanya is, in many respects, little more than a "regular" person who wanted nothing more than anyone else - namely, to be happy, albeit on her own terms and without regard to the happiness (or even continued existence) of anyone else.