NCIS: Los Angeles will dive into the new season with a healthy dose of danger.

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Well, it may not be quite so healthy for Callen and Sam. The duo will be fighting for their lives when the CBS drama returns with "Deep Trouble: Part 2," NCIS: LA's follow up to their season 5 cliffhanger.

"We pick up where we left off last season," said Daniela Ruah (Kensi) on Extra. "Callen and Sam (played by Chris O'Donnell and LL Cool J) are in grave danger. They're stuck in this submarine and the whole team is trying to get to them and they're out of contact."

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Luckily for Sam and Callen, Deeks and Kensi will quickly take to the air in order to track down them down. In the meantime, however, the bomb-laden sub will begin to take on water and Kensi may have it out with DEA Agent Talia (Mercedes Masohn).

"Awesome week on #NCISLA, they gave me great script, a submarine, helicopters and a chick fight," tweeted director Dennis Smith during filming last May. "Happy Director :-)"

Find out more when NCIS: LA returns to CBS on Sept. 29 at 10 p.m. ET. Click the video below to see a clip from the season 5 finale, "Deep Trouble."

Tags: NCIS: LA television NCIS: Los Angeles CBS