The CSIs investigate the murder of a news anchor, Theresa Shea, who was killed during the filming of a live news broadcast. Theresa was killed by a precise stab wound to the back of her neck, and no one saw the injury because the power went out in the news room for twenty seconds. The CSIs investigate the evidence available to them, which is minimal and points to someone with military experience and a knowledge of the ins and outs of the station. When the murder weapon turns up in the possession of mentally unstable Denny Jones, the lighting tech, he kills himself to avoid going back to jail. Russell, not convinced that Denny was the real killer, has the team recreate the murder in the darkness of the newsroom, where they discover that the producer, Fred Paulson, was the only one who had the time to kill Theresa in the twenty second window. Sara discovers that Theresa had uncovered crimes in Paulson's past, and he decided to kill her to protect himself.