NCIS: Los Angeles' is pairing a highly anticipated Densi reveal with some major Deeks trouble in "Fighting Shadows," but will they be connected?

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Hetty (Linda Hunt) will rearrange her team in episode 18 (filming as episode 18), pairing Kensi (Daniela Ruah) with Sam (LL Cool J) and Deeks (Eric Christian Olsen) with Callen (Chris O'Donnell). The sudden change will set off alarm bells in Deeks and Kensi's heads, but the pair may have even more pressing problems.

"What has Deeks done? Even Hetty is in a quandary," executive producer John Peter Kousakis teased. "Who is tailing Kensi? It's a Deeks mystery. Does Hetty know?"

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Olsen previously stated that the Densi relationship could cause a multitude of problems, and these may start to manifest as season 6 comes to a close.

"We make decisions based on what's in the best interest of the country or the mission, and everything kind of flies out the window when you become so emotionally invested in your partner," Olsen said, according to TV Guide. "Now [Deeks] has this realization that [Kensi] is the most important person in the world to him. And I think it's going to be the catalyst for a lot of mistakes."

Find out more when NCIS: LA airs Mondays at 10 p.m. ET on CBS. Click the video below to see a preview for the series' next episode.