A Navy Lieutenant Commander in charge of a shipment of nuclear weapons disappears under mysterious circumstances and the possibility that she was abducted results in Gibbs and the team being summoned into the office on a Sunday to save the Commander. During the investigation, they dig into the Commander's life and discover that she was a member of an organisation dedicated to combating online pedophilia and that her intended target might have been responsible for her kidnapping, only to discover that an unlikely figure is truly responsible....