NCIS: Los Angeles is testing Deeks emotions, and a DEA agent may be to blame.

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While Kensi (Daniela Ruah) continues her overseas search for the White Ghost, an explosion at a fishing wharf will put Deeks (Eric Christian Olsen) and the team in contact with an undercover DEA agent named Nina/Talia (Mercedes Masohn). Unsure if the crime was an act of terrorism or merely a smuggling deal gone south, Callen's (Chris O'Donnell) crew will be sticking close to the ocean in "Fish Out Of Water."

However, someone associated with the case will be causing a few problems for Deeks.

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"515 spoiler: Deeks works a case with someone who challenges his feelings. Will he stay true. #staytuned #NCISLA," teased executive producer John Peter Kousakis.

Could Nina/Talia cause Deeks to question his feelings for Kesni? The DEA agent will be sharing quite a few scenes with the LAPD detective, a fact which makes her a prime suspect in the case of Deek's conflicted feelings (see gallery above).

Kesni, however, will have something else on her mind entirely. Teamed up once more with Granger, the NCIS agent will have her hands full investigating a helicopter crash they may be related to the White Ghost.

Find out more when NCIS: LA airs Tuesdays at 9 p.m. ET on CBS. Click the video below to see a preview for the series' most recent episode, "War Cries."