"Viral" -- When a petty officer's murder matches the M.O. of a local serial killer, the NCIS team must determine if this is the killer's latest victim or the work of a copycat, on NCIS, Tuesday, Oct. 27 (8:00-9:00 PM, ET/PT), on the CBS Television Network. Pictured left to right: David McCallum, Sean Murray, Emily Wickersham and Mark Harmon Photo: Monty Brinton/CBS é2015 CBS Broadcasting, Inc. All Rights Reserved