Robin Cook's name is synonymous with medical thrillers. He's landed many books of this kind on the national charts over the last two decades. His latest, Shock , focuses on subjects that are in the headlines—embryonic and stem cell research. Putnam launched the book with a 12-city bookstore and media tour that includes an interview with Cook on CBS-TV's Early Show. Total copies in print: 225,000.

A newer bestselling author to this genre is Tess Gerritsen; her latest, The Surgeon , enjoys a second week on the PW list. It's her first book with Ballantine, and the publisher began its promotional push by sending out special reading copies carefully zipped into miniature body bags. She kicked off an 11-city national tour on August 25 with stops in Camden and Augusta in her home state, Maine. She will be on tour through mid-October. There are 90,000 copies in print.