NCIS: Los Angeles Episode 4.22 Raven & The Swans

When a woman is stalked in a parking garage and almost killed by three men, Hetty assigns the NCIS:LA team the case, but gives them almost no information to work off of. Callen quickly realizes that Hetty is clearly protecting the unknown woman's identity, so he confronts her and she eventually admits that the woman is another NCIS agent named Grace Stevens. Grace was recruited as an orphan, much like Callen, and has been undercover trying to get intel on a suspected nuclear arms dealer named Nolan Vanderhoos. Stevens suspects that the three men who attacked her were Vanderhoos henchment. After a failed hotel sting to capture intel, Callen comes up with a plan to use Grace as bait to catch Vanderhoos. They plant a newscast with her picture saying she's recovering from the parking garage attack at a local hospital and remains unidentified. This brings Vanderhoos and his team in immediately, allowing the NCIS:LA team to make the arrest.