Secrets Revealed

When a strange young girl by the name of Keira shows up at NCIS Los Angeles headquarters, different sides of Hetty and Granger start to show. What secrets and dangers does she bring with her? And what part of the past do Keira, Hetty, Granger, and her best friend Dimitri share? How will Keira's time in L.A. affect and help the NCIS L.A. team?