​NCIS: LA Boss: Uncovering the Mole Will Have "Catastrophic Results"

NCIS: Los Angelesis getting shaken up in a major way.

In the Season 8 premiere, Hetty (Linda Hunt) and Granger (Miguel Ferrer) got an unexpected visit from Undersecretary Corbin Duggan (Jackson Hurst) and other higher-ups from Washington, who descended on NCIS: LA headquarters in order to sniff out a mole working within the agency.

If that wasn't enough, Kensi (Daniela Ruah) was gravely injured during a rogue mission to Syria when the chopper in which she, Callen (Chris O'Donnell), Sam (LL Cool J), and Deeks (Eric Christian Olsen) were returning in got bombed on their way back. While they were awaiting rescue, the group got ambushed by a local army, and managed to escape only after Granger ordered Eric (Barrett Foa) and Nell (Renee Felice Smith) to take out the group with an air strike from a drone, using Duggan's name.

At the end of the episode, Hetty sacrificed herself for the rest of the team, giving Duggan a signed confession admitting that she's the mole, and was escorted out of the office in handcuffs. Kensi, meanwhile, remains in a coma, getting ready to undergo a CT and an MRI.

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So, where does the team go from here? First of all, don't expect Kensi's recovery -- if it happens at all -- to be a quick one. According to NCIS: LA showrunner Scott Gemmill, Kensi will be "out of commission for potentially forever, but for an extended period of time at the very least."

And with Kensi and Hetty out of the picture at least for the time being, the team will look to some unlikely sources for backup. "The remaining members of our team sort of have to step up," Gemmill tells TVGuide.com. "So we'll see some different partnerships. We'll have some people perhaps brought in, new people to work with. And people like Nell will find themselves doing some more field work than they're used to."

Next week's episode will provide a solution to some of the "leadership issues" the team is facing, Gemmill says, but it won't be long before the mole issue rears its head again. And when it does, it's actually Sam who will be affected by the ripple effects "in a very strong way."

"It's a temporary solution," Gemmill says of Hetty taking the fall. "Our people only have so much time before it will be revisited. ... [They] will be given a little more time to resolve this, and they ultimately will by the end of the season - but with some catastrophic results."

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

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