Remote. Peaceful. Picturesque. This is how the Mumford Mountain Hotel bills itself in its brochure. And it lives up to this description- most of the time. But this year, the hotel is hosting a prestigious conference for the study of forensic science, and the organizers have extended CSI head Gil Grissom an invitation he can't refuse. Joined by fellow investigator Sara Sidle, Grissom leaves the department in the capable hands of Catherine Willows and heads east. But he and Sara soon find themselves in all too familiar territory- and back in Las Vegas, Willows and the CSI team have uncovered trouble of their own.