Cryonics medical technifiction in the Michael Crichton vein but--despite the title--more thriller than horror chiller. A ``chiller'' is the dismissive name for frozen folks who await resurrection when medical science can deal with their once- fatal problems. Biochemist Alex Cowell runs Immortality Incorporated in Orange County, California, and has about 36 clients on ice, including his dog Sparkle. But he and Dr. Susan Hagerty--a researcher who's developed a transglycerol that avoids cell rupture (or freezer burn) during superdeep frigidity--bring Sparkle back from the dead after first having alleviated his spinal tumor with surgery that the dog could not have withstood while alive. Sparkle is the first major success in cryonics. Vitality Incorporated, meanwhile, a rival group that secretly has the bodies of John Wayne, Howard Hughes, Peter Sellers, and others on ice, is a registered archival tissue bank that does cryopreservation research--except that it's really a scam run by two religious phonies out to sucker millionaire celebs. Its chief phony, Dr. Lomax, once revived 12-year-old George, an orphan who drowned in a frozen lake. Then patches of George's brain went blooey, and as George grew older in foster homes, he became a body-builder, a credit-siphoning computer hacker, a religious fanatic, and at last a serial killer. The two phonies finally get terminator George under their control and sic him onto Immortality Incorporated. The reader may well wonder what's happening after George murders Alex, Susan, and their assistant Kathryn. But then the story leaps ahead 38 years, and the trio of dead researchers is brought back to life in the next century! And crazy George, much older, is still around, as are the two phonies, who've managed to join Immortality and Vitality into one group.... A nicely paced debut that holds up throughout, though George's misdeeds as a credit thief are far more compelling than his kill- sprees.