McLeave has written zippy suspense and solid medical novels; he combines his two interests in this suave tale of spying on the Chinese-Indo-Pakistani border. Research bacteriologist Paul Brodie, a prickly Scot, is also an undercover agent for the SIS, which has noted some strange ice-melt on the Tibetan roof of the world, the Hunza Valley, where three major powers and six states come together and join borders. Though sent to discover the source of these avalanches and strong seismic readings (obviously nuclear testings by the Chinese), Brodie soon finds that his real object is to penetrate the tightly secured germ warfare laboratories where Chinese bacteriologists are working on new viruses. Nomadic traders have brought a strange disease into the Hunza Valley, and now the World Health Organization has sent in a medical research team to look at the new virus. This quarrelsome team, headed by beautiful Shane Kingslake, is soon trying to find a vaccine to fight the virus. In searching for the sources of the epidemic, Brodie and Kingslake run afoul of the Chinese military and are themselves made guinea pigs for viral infection. Intelligent thriller work--with the extra plus of fascinating medical details on viruses and vaccines.