Grissom and his team return to duty after long and bad bouts of the cold. DA Maddie Klien calls on Grissom to be an expert witness for a grand jury investigating La Tijera ("The Scissor"), a very dangerous Las Vegas gang. The gang appears to be terrorizing and murdering witnesses who could land them in jail. Grissom is reluctant, but Maddie insists he is the only one for the job.