Choppy, ditsy tale of a Gen-X slacker on the trail of a homicidal hacker who uses exploding floppy disks to eliminate fellow hackers who blunder through the ``back door'' of a data- encryption program. Coming off their nonfiction exposÇ of the hacker elite, Masters of Deception (1995), technology journalists Quittner and Slatalla deliver a cumbersome, talk-soggy cute-kids-in-peril adventure that often reads more like a niche-marketed YA. Harry Garnet, having failed to land a permanent job with a Syracuse firm after graduating from law school, is content to let another lazy summer slide by living in the Adirondacks and doing odd jobs around a nearby lakeside resort. One morning he innocently delivers a package containing a fatal floppy disk to math professor Frederick Ames and his slender, red-headed archaeologist daughter Annie. The disk explodes inside the professor's computer, killing him and putting Garnet in the hospital. Fascinated by Annie, Garnet later follows her to Manhattan, where he discovers an ``urban crypto militia'' that hangs out at Cafe Info, a computer-wired restaurant. There, he's befriended by the wealthy and pony-tailed Lionel Sullivan, a software designer who thinks that some madman is blowing up innocent computer geniuses who, like Professor Ames, have found a deadly flaw in a data-encryption program called Patriot, designed to protect user privacy on the Internet. Garnet agrees to use his untried legal skills to stop Patriot before a congressional subcommittee votes to impose it on the cyber community, while Sullivan helps him and Annie navigate a virtual- reality maze to find the killer. Quittner and Slatalla describe their hero's hapless heroics with a fey insouciance that becomes as cloying here as in their previous psychokiller whodunits (Mother's Day, 1993; Shoofly Pie to Die, 1992). Some fascinating cyber-scenes about how distinctive personality traits seep through the most impersonal computerized disguises, but abundantly clunky dialogue and cutesy asides stall the suspense.