It's time for Deeks to face the music on NCIS: Los Angeles.

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The detective is under investigation by the LAPD's office of internal affairs, and according to Spoiler TV, viewers will finally find out why in episode 9.

Set to air on Nov. 23, "Internal Affairs" will see Deeks (Eric Christian Olsen) biggest secret exposed, and according to Olsen, it could be darker than anyone ever expected.

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"It's tough," says Olsen told Entertainment Weekly. "I think he's covering something up, something catastrophic. I think he probably gets sent back to LAPD at some point. I think he's hiding it from everybody, he's been hiding it from himself. Whatever it is, I only hope he did it for the right reasons."

Fan can rest assured, however, that the unpleasant incident will be completely flushed out by time the winter hiatus begins.

"When the internal affairs investigation reaches its conclusion and we find out what's behind it, what it's all about, it will be a catalyst for at some point Deeks making decisions about his future," series creator Shane Brennan explained to TV Guide. "Before we reach the halfway point, the whole internal affairs issue will be well and truly investigated."

It is currently unknown if "Internal Affairs" is a retitling of Dave Kalstein's "The Long Goodbye."

NCIS: LA airs Mondays at 10 p.m. ET on CBS.

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Tags: NCIS: Los Angeles NCIS: LA television CBS