NCIS: Los Angeles' little mole problem has escalated, big time.

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Granger (Miguel Ferrer) is in the hospital during "Traitor," and it's up to Callen (Chris O'Donnell) and his team to figure out who put him there.

In a new sneak peek, Callen and Sam (LL Cool J) visit the site of Granger's car accident and reveal some disturbing clues (see video below). Not only was the Assistant Director favoring the gas pedal, but a lack of skid marks from his one car collision indicate that he didn't even attempt to stop.

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So what had Granger 15 miles from home and clearly put of control in the middle of the night? As far as Callen and Sam are concerned, the suspicious accident is even more proof that the Office of Special Operations has a mole.

Hetty (Linda Hunt) has the same idea, and soon their secret headquarters is in lock down. Unfortunately for the team, the mole may be locked in with them.

"Keep your eyes open and your wits about you today," Hetty cautions her team.

So who is the mole? Find out more when NCIS: LA airs Mondays at 10 p.m. ET on CBS.

Tags
NCIS: LA, Television, CBS, NCIS: Los Angeles