Even in its 18th season, the NCIS team proves they still have some surprises in store. Forensic psychologist Jack Sloane, played by Maria Bello, had her final episode on NCIS, exiting the show during Tuesday's episode, and fans are still reeling. In the episode, Sloane revealed to Gibbs (Harmon) that she's saying goodbye to the investigation team for the peaceful life of Costa Rica –– in fact, she'd already placed a bid for a home in the South American country. The brief moment is interrupted by the sobering news that a school bus carrying four young girls was kidnapped by the Taliban in Afghanistan. The bus carried a message on the side: "SLOANE NCIS."
Sloane immediately jumps into action, recognizing the clue was given to her by Darya, a "chaperone" and fellow captive who helped the psychologist when she was kidnapped in Afghanistan by "The Monster." Before she can even ask, Gibbs promises her she'll be transported to the location to investigate. The two begin working with a man named Nadi as they attempt to find the girls' location. At one point, the crew begins to suspect Darya was an accomplice to the abduction until the team discovers a live stream of the girls being auctioned off. One of the girls gets returned for epilepsy, and therefore of no value. Shortly after, Darya winds up in the village dead and thrown from a moving truck. The captors left her body with a note: "Go home or there will be more blood." Sloane breaks down at the tragic loss. “She wasn’t in on it, Gibbs! We couldn’t see her basic act of humanity for what it was. I’m out. I’m done,” she says.
Gibbs quickly discovers Sloane's real plan is to leave on her own to find the girls. “You can’t ground me when you don’t like the plan,” she says. “I can when I want you around,” Gibbs responds. “On NCIS, or on the planet?” she asks. “Both,” he states. Gibbs then demands two things: waiting for sat recon and hopefully some backup, and joining her.
In the states, the team quickly gets ahold of a hacker who owes them a favor. They convince him to share the girls' location with the team, who then hands it over to Gibbs and Sloane. The duo comes in with a team of Marines and rescues the kidnapped four.
However, the celebration is followed by heartbreak. Gibbs realizes Sloane may be leaving, but she's not going to Costa Rica as she previously said. Sloane decides to stay in Afghanistan and continue the work Darya started. “I did say I needed a change!” she says.
"I have loved my time with NCIS," she explains. "You don’t need me anymore. To which Gibbs responds, “I’m not sure about that.” Sloane explains, “I don’t belong behind a desk. Never did. And you’re right, I was running, and I don’t want to anymore. I want to make a difference here.”