7 years ago, Ari murdered Annabelle Todd's big sister, Kate. After the case she resigned from NCIS, and accepted a job at the FBI. When the decomposed body of a Navy Officer is found and taken to the Jeffersonian, her partner Seeley Booth, calls in the NCIS MCRT, without her consent. How will Annie react to seeing her old team, and why is one of them not surprised to see her there?