Saul's 12th horror novel in 12 years--an undemanding but slick tale of biological tampering that matches the relative best of his huge-selling mass-market paperback originals (Suffer the Children, Nathaniel, The Unwanted) and that far outpaces his one previous hard-cover, The God Project (1982). There might be a new idea somewhere in this brisk story of a mad doctor toying with teen-age boys' hormones to produce homo perfectus (and the occasional Neanderthal-like boo-boo), but it's hard to see for all of Saul's useful borrowings from Frankenstein, The Island of Dr. Moreau, much of Robin Cook, and Ira Levin's The Stepford Wives. Moreau is played here by Dr. Marty Ames, who conducts his lunacy under the guise of providing ultrahigh-tech athletic training for the high-school teams of Silverdale, Colo., the Rocky Mountain R&D headquarters of the giant Tarrentech Corp.--which hopes to profit from Ames' wacky treatments of organic disease. Ames' eyes gleam when runty Mark Tanner, stunted by rheumatic fever, moves to town, and before long Mark's spending time at Ames' lab and growing inches and muscles just like the other guys at Rocky Mountain High. But like too many subjects of Ames' unperfected techniques, Mark grows a whopping temper and fang-like teeth, too, and soon is staying out late and strangling the family dog. And as if that isn't enough to worry his stalwart mom, Saul's heroine, then just wait until she sees him loping around the lab with two fellow apeman who are busy maiming and killing. Cruise control all the way. Of interest is the astonishing fact that the publisher is charging a dollar less for this hard-cover than for the author's 1982 one, which they also published; this deflationary pricing, plus a promised 100,000 printing and big ad campaign, could give Saul his first hard-cover best seller.