Though its teenage characters spend a fair amount of time zipping at high speeds through cyberspace, this bizarre futuristic tale starts off Tom Clancy's Net Force series at a sluggish pace. Set in 2025 Washington, D.C., the tortuous plot centers on Matt Hunter, a member of the Net Force Explorers, the ""young people's auxiliary"" of an organization that polices the global computer Net. Attending an Orioles' baseball game in hologram form (""Implants beneath his skin connected him to the world Net, allowing his image to be seen here""), one of Matt's pals is shot by a holographic bullet fired by one of four virtual vandals who have assumed the identities of individuals from the past. When Matt hears that the quartet may be the same teens who, under the control of a mysterious computer genius, have been infiltrating computer systems and injuring people hooked up to them, the cyber sleuth sets out to learn their true identities and their plans. It's a laborious quest and Matt's puzzlement at the perpetrators' mission pales next to readers' confusion. Abandoning the realm of computers in the final chapters, the novel picks up speed with an old-fashioned chase scene in which Matt and cronies best the bad guys. Computer addicts may get a charge out of this pseudo-reality, but most of the serpentine story's action is a virtual washout. The Deadliest Game, also published this month, is the second installment ($4.99 paper -16174-9). Ages 12-up. (Feb.) FYI: An adult series based on Net Force is being released simultaneously (Mass Market Forecasts, Jan. 18); Net Force is based on an ABC mini-series.