The reason for Sherlock's (Jonny Lee Miller) unexpected arrest will be finally revealed on the next episode of "Elementary" season 5.

In the previous episode titled "Wrong Side of the Road," Sherlock was suddenly arrested by a member of the Defense Intelligence Agency (DIA) even if he could not remember what he did wrong.

But in the teaser for the upcoming episode called "Fidelity," it is revealed that the former Scotland Yard consultant was only abducted by DIA Agent Anson Gephardt (Scott Shepherd) to encourage him to think about his future. This could mean that the agent wants Sherlock to join him.

On the other hand, the synopsis for the episode reveals that Joan (Lucy Liu) and Sherlock's protégé Kitty (Ophelia Lovibond) will realize that a series of murders that Sherlock and Kitty solved in London in the past could be linked to an international government conspiracy where the DIA could also be involved.

But could this also serve as the last case that Kitty will deal with together with Sherlock and Joan after revealing that she already has a child.

In the previous episode, Kitty told Joan that she just wants to work with the anti-human trafficking group as a counselor. But she was also worried that Sherlock will not approve of her decision.

Kitty reminded Joan that Sherlock spent an entire year to train her for the job, and he was very serious about it. This made her more concerned that her resignation would make him very disappointed.

"He taught me, he gave me structure, he gave me purpose. This thing we do, this isn't just a job to him. It's something much more, and I'm just gonna turn my back on it? I'm scared he's going to be disappointed," Kitty said to Joan in the past episode.

Will Kitty push through with her plans now that Sherlock's life is put in danger?

The next episode of "Elementary" season 5 will air at 10 p.m. EST on Sunday, March 12.