Leroy Jethro Gibbs (Mark Harmon) will be tested once again in the upcoming NCIS season 18 episode 10. The character has dealt through a lot already but more problems are coming for him along the way. This time, he finds himself being arrested -- though the exact reason is yet to be seen.

NCIS season 18 episode 10 comes with the title "Watchdog," and it sees Gibbs in another complicated situation. The promo showed an officer saying that he is under arrest for aggravated assault and the clip ended with his colleagues who were all shocked he's being taken at the precinct.

At the moment, it is unknown what Gibbs exactly did that led him to be arrested. But then, there are a lot of reasons that may have impacted his actions and caused him to make drastic decisions. He's going through something over the past few episodes and this might have been contributed to what's happening to him.

For instance, Gibbs is still dealing with the departure of Jack Sloane (Maria Bello), who decided to stay in Afghanistan. Then, in the previous episode, Tobias Fornell's (Joe Spano) daughter died. Harmon's character knows the pain of losing a daughter since he experienced this firsthand.

This might have triggered some painful memories in the past, prompting Gibbs to do some unexpected actions. It is unlikely that Gibbs did something crime-related, especially since he honors the law so much. There's also a possibility that he was just falsely accused or broke a law that's why he got arrested.

Also, the synopsis of NCIS season 18 episode 10 noted that the team discovered a secret dogfighting ring. Because of this, one of them made an unexpected move. Gibbs might be the member who did something that jeopardized the operation, as well as his job.

Considering his current situation, he possibly likes to do this mission alone to have more alone time for himself. After everything that happened as of late, he might bring back some parts of his old self -- including not opening up to others about the things he's facing at the moment.

Meanwhile, NCIS season 18 episode 10 is, reportedly, the last one before the police procedural goes on a hiatus once again. The installment may leave some cliffhanger, particularly to Gibbs' arc, making fans more excited to see what's coming next for the character.

NCIS season 18 episode 10 is scheduled to air on Tuesday, March 16, on CBS.