The investigation to figure out who the (real) mole is on NCIS: LA heated up recently after the team tracked down Natalie Grant, aka Amber Wilcox, handler of former NCIS: LA employee and secret-spiller Karl Brown.

We're still waiting to figure out who they're really working for and who the mysterious "Ray" is, but LL Cool J, whom TVGuide.com caught up with recently in Los Angeles, says we should not expect the answers to be as clear-cut as we might be thinking. Word is, a series of events is about to lead to a big, humdinger of a three-part crescendo that'll end with major upheaval, and we're unlikely to see any of it coming.

Catch up on all this week's Mega Buzz!

"There are multiple moles that are trying to destroy the agency," said the actor, who plays Agent Sam Hanna. "They're actually closer than the fans would even expect and that's going to lead to major changes." How major? "It affects the cast" and leads to a "changing of the guard."

NCIS: LA airs Sundays at 8/7c on CBS.

(Full disclosure: TVGuide.com is owned by CBS.)

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