A devastating NCIS: Los Angeles premiere will leave two members of the OSP team out of commission.

Callen (Chris O'Donnell) and co. will return to action this Sunday, kicking off season 8 with a two-hour premiere. Unfortunately, the events of "High Value Target" and "Belly of the Beast" will take their toll. When the hunt for the mole intensifies, Hetty (Linda Hunt) will find herself stuck in Washington even as a mishap in Syria leaves one her own in the ICU. It will be with troubled minds that the remaining members of the NCIS: LA squad head into episode 3, "The Queen's Gambit."

"The NCIS LA team investigates an abduction case while down two members, with Hetty being held in D.C. for questioning, and another still in the ICU following the mission in Syria," CBS teased.

The combination of Daniela Ruah's (Kensi) maternity leave, her absence from all episode 3 photos, and the return of Agent Blye's mother confirm suspicions - she will be the one to end up in a hospital bed by the end of "Belly of the Beast."

"My pregnancy has brought on reasons to hide the pregnancy, which has then inspired a very particular storyline this season - at least in the first half of it, that's all I know - where something very drastic happens to the whole team," Ruah told EnStars. "Kensi is affected by that a little bit more, and that poses obstacles and a big long trajectory for Kensi and Deeks."

By the time the credit's role on "Queen's Gambit," viewers should expect the mole investigation to come to a head.

"The first three episodes are like a freight train, and the mole is the catalyst for all of that," Eric Christian Olsen (Deeks) teased at San Diego Comic-Con. "The mole gets very real, very quickly."

Are you ready for season 8? NCIS: LA will return to CBS on a new night and time this Sunday at 8 p.m. ET. Click the video below to see a preview.

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