TV: Person of Interest - Zero Day (Sneak Peek)

Reese and Finch realize that a virus has rendered The Machine erratic, causing it to issue numbers irregularly. As they race against the viral countdown, the team searches for a tech millionaire so elusive no one has ever seen him. Also, Detective Carter's mission to bring Cal Beecher's murderer to justice lands her squarely within the sights of the HR criminal organization on the next episode of Person Of Interest airing Thursday at 9/8C. Carrie Preston, Amy Acker, Sarah Shahi, Brett Cullen, Jay O. Sanders and John Nolan guest star. Only CBS