Join the little-known and even less understood heroes of police work in Las Vegas -- the Crime Scene Investigation squad-- as they battle to solve a gruesome and baffling case. A package, bearing no return address, arrives at the Anthropology Department of the University of Nevada in Las Vegas, where a shocked staffer discoves a genuine shrunken head inside. At first they assume it to be a historical relic -- until Gil Grissom and his remarkable team of forensic investigators establish that it's an all-too-recent murder, and that a serial killer with a distinctly unusual M.O. is on the loose.