On NCIS Season 12 Episode 18, a woman is murdered in the garage of a home belonging to Marine Gunnery Sergeant Holt Perkins. Perkins is relieved when he arrives home and discovers that the woman is not his wife. Abby discovers that the woman is a thief named Mallory Bleaker. She also determines that Bleaker was in the process of robbing Perkins' house while he was stationed out of country. When Ducky finds a paper with the symbol of a dragon's tooth on it, Delilah is consulted. At that point everyone realizes that the death of the thief had nothing to do with theft at all. The symbol is an emblem of a terror group, who has been targeting military homes. Only the group turns out to be just one person named Omer Malik and his accomplice. As NCIS joins forces with Homeland Security, they discover that the terrorist has been breaking into the homes of military people, and making just a few minor changes to show that the houses have been invaded. During that time he has taken video of his escapades, which he intends to eventually upload to the internet. His purpose is to cause fear, and to make the military families feel that they're not safe in their homes. Meanwhile, McGee is angry that Delilah has been on American soil for a week and hasn't told him. He's also worried that Delilah's boss is getting too friendly with her. Things come to a head and they have an argument. Then there's a knock at the door. Who's at the door? Will McGee and Delilah survive their confrontation? How will the terrorist be caught? You can find out all this and more when you watch NCIS online.

Reunited - NCIS

McGee and Delilah are reunited during an investigation on NCIS. "Status Update" is the 18th episode of the show's 12th season.
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NCIS Season 12 Episode 18 Quotes

McGee: Why did you move half way around the world?
Delilah: Why did you let me?
McGee: Because I love you.
Delilah: I know.

Delilah: Rule number 9. I listen. You and I on the other hand...we need to work on our communication.
McGee [kisses her]: Hello.
Delilah: Hi.