""Buffy the Vampire Slayer""'s James Lurie brings his rich, honeyed baritone to Prestons book of essays on radical science. The book is rather uneven. The first chapter is an overly self-referential account of Prestons own laboratory encounter with the Ebola virus he made famous in ""The Hot Zone""; the other essays are more traditional portraits of scientists on the frontier of discovery. Lurie conjures an engaging and credible Russian accent when speaking for two immigrant mathematicians who are racing to determine all the digits of pi. But he is inconsistent and strained when attempting a genetics researchers British accent. Still, listeners will enjoy the way both Preston and Lurie uncover the humanity of great researchers, whether they are attempting to save hemlock and chestnut trees from fast-encroaching diseases or help those suffering from Lesch-Nyhan syndrome, a rare condition that causes its victims to compulsively consume their own flesh. ""A Random House hardcover (reviews, Apr. 21). (June)"" .