'NCIS' Season 18 Episode 8: How and Why Jack Sloane Left the Show On 3/3/21 at 3:49 AM EST NCIS Season 18 has been dropping hints for the last few episodes that Jack Sloane (played by Maria Bello) was ready to move on, with the forensic psychologist saying she was moving to Costa Rica. However, her final episode (Episode 8, "True Believer") revealed a change of plans. The Sloane-centric episodes of the CBS procedural began with Sloane telling Gibbs (Mark Harmon) that she had put an offer on a Costa Rican house. This announcement, however, was interrupted by news from Afghanistan that the Taliban had hijacked a school bus—and someone had written on its window "SLOANE NCIS."