In "The Policeman's Daughter," McCarthy creates a world in which death has ceased to exist. Through the technology of "fax machines," which in McCarthy's world, are kind of a cross between Replicators and Transporters from Star Trek. They can copy and transmit anything, including human beings. In addition, copies of anything, including human beings, can be saved in "hypercomputers" (really dumb word, I know) indefinitely. Essentially, this means that people can live forever, making new copies of themselves as needed, sometimes existing as several copies at once in order to multitask. A new state of deathless "immorbidity" ensures. It's a little cheesy, but interesting nonetheless.
What I really like about this story, however, is that McCarthy has decided not to focus on how immortality would affect the way people act. It is in there a bit, of course, but it certainly isn't the focus of the story. Instead, McCarthy asks the question "If death doesn't exist, does that mean that murder also ceases to exist?" Of course, copies can be killed, and people arn't impervious to injury, but, if a new copy can just be made, is it really murder?
In a style reminiscent of old noir stories, this is exactly the question that Carmine Strange Douglas, Esq., renowned lawer of "strange cases," is faced with when his old university friend, Theddy, shows up unannounce at his office one day. Theddy wants to elist Carmine's services because he believes that he is trying to kill himself. More specifically, an earlier version of Theddy from 70 years ago (when both he and Carmine were in their 20s), is now trying to destroy all the current versions of Theddy. The story revolves around the figuring out why, and how Carmine can solve this problem. It's a great twist on the detective story, and even involves a great romantic sub-plot that involves the titular policeman's daughter. All in all, and enjoyable twist on the genre.