During a confidential meeting in MTAC, sensors picked up an unauthorized electronic transmissions. A bugged pen was found on SecNav Porter, who received it as a free gift in a solicitation for charity mail at home. Abby discovered that it had been actively listening for 30 hours, during which time Porter had attended three classified DOD briefings. This scenario had been predicted two years earlier by NSA Agent Eleanor "Ellie" Bishop. Gibbs decided to bring her into the investigation. It turned out that a weapons manufacturer who'd been shortlisted for the SecNav job had sent the bugged pen to Porter, in order to discredit her.