Stabler ends out being out of commission after a perpetrator high on PCP throws him through a window at the station, so Benson teams up with Munch and Tutuola to investigate a mysterious packet of photos. The photographs lead them to both a suspected child pornographer and a junkie burgler, but after Benson takes ill during the investigation, the team realises that there is more than child pornography at stake as their investigation soon reveals that Seth Millstead wasn't into little boys at all, but had been using the tenants of the apartment building in an experiment for a new pesticide.
After catching an international arms dealer, the NCIS team learns that Navy's highly classified weapons system will be sold to "La Grenouille," an important arms dealer. To stop the transaction, the team will send Ducky undercover. Meanwhile, another government agency appears to be working on the same case, with different plans.
Debbie's glad to have her dad back at home, but Monica's not happy with all the attention Frank is giving her and tells her it's time she found herself a boyfriend. Also Ian catches the eye of someone he least expected.
Stephen receives a message from Master Media International that they would be praying on his behalf on February 22. This is followed by the 40th installment of Better Know A District (Ohio's 18th with congressman Zack Space).
The mission is to take control of a South Korean submarine to assist in the defection of a North Korean Scientist. The team find themselves confronted by several roadblocks. On the submarine, the South Korean Captain does not want to take orders from Jonas. On the home front, Kim has a dream that shares many similarities to the current mission. Ryan thinks that Bob told Kim about the mission and threatens to scrap the mission and wants to fire Bob.
The team is sent into Iran to set up a system that can detect Weapons of Mass Destruction. The mission goes off kilter when civilians become involved.On the home front, Tiffy runs into a dilemma while doing her community service. Molly and Kim are helping Jeremy and are confused by Crystal's behaviors. Mack finds himself in trouble.