'NCIS': Why Gibbs Is Behind Bars in Emotional New Episode

The preview for the next episode of NCIS surprisingly features a scene with Gibbs getting arrested. It's not clear exactly what he did that will lead to his arrest, but the episode centers on a dogfighting ring case. The episode follows a series of shocking moments during the show's 18th season, which airs Tuesdays at 8 p.m. ET on CBS.

In the 20-second preview for "Watchdog," Gibbs (Mark Harmon) is read his Miranda rights as he is cuffed and taken out of the NCIS office. He was told he was arrested for "aggravated assault." In one scene, Gibbs told the team to make sure they tell the truth. "Tell the truth to who?" a puzzled Eleanor "Ellie" Bishop (Emily Wickersham) asks him. Another brief moment shows Ellie yelling after Gibbs. It's possible that the "unexpected move" made by one of the NCIS team members mentioned in CBS' episode description is what lands Gibbs in trouble during their investigation of a dogfighting ring.

NCIS fans have been through the emotional wringer this season, thanks to multiple character deaths and one major departure. This week's episode, "Winter Chill," revealed that Emily, the daughter of Tobias Fornell (Joe Spano) died. Emily has struggled with addiction in the past, and it ultimately took her life. At the end of the episode, Fornell called Gibbs to let him know that Emily was rushed to the hospital after she was found unconscious with pills around her. Unfortunately, she could not be revived when she was taken to the hospital. After Emily's death, Director Leon Vance (Rocky Carroll) read Merritt Malloy's poem "Epitaph," ending the episode on a tear-jerking note.

The March 2 episode, "True Believer," was Mario Bello's last episode. Bello played forensic psychologist Jack Sloane, who was introduced in Season 15. In July, news that Bello would leave the show leaked and fans had to wait until this month to see how that departure would play out. In "True Believer," she planned to leave the NCIS team for greener pastures in Costa Rica and had already bid on a house there. However, she scrapped her plans in order to go to Afghanistan to help rescue young girls who were kidnapped by the Taliban.

The future of NCIS itself is unknown, even as CBS prepares to launch another spin-off, NCIS: Hawaii, and announced the cancellation of NCIS: New Orleans. Last month, sources told The Hollywood Reporter that Mark Harmon's contract ends with this season and it would be difficult to imagine the show without him. After Harmon heard CBS would end the show without him, he reportedly started talking with CBS about returning for a few episodes so the show could get a 19th season.