Agents Hunt Expert Knife Fighter on 'NCIS:LA'

The investigators on NCIS: Los Angeles have seen a lot in their time, and have been in many fights for their lives, but never have they had to battle so hard than when they face down against an expert knife fighter.

In the coming episode of NCIS:LA, headless corpses are turning up all over the city, and it's up to Agent Callen (Chris O'Donnell) and Agent Hanna (LL Cool J) to stop the man responsible. The only problem is, the possible killer is a hardcore warrior known as a Gurkha.

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Gurkha's are skilled knife fighters from Nepal, used in many wars and renowned for their speed, their killing talent and their toughness. But the NCIS:LA agents might just need to work with the Gurkha to get back a very important stolen hard drive.

ET visited the set of NCIS:LA during the filming of this action packed episode, and talked with the cast and crew about what it was like training for such exciting combat sequences, and what to expect from the exciting fight choreography.

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Check out the video for a behind-the-scenes look at one of the episode's most-exciting knife-fighting sequences, and hear from the stars of the show about what it took to make this episode work.

This episode of NCIS: Los Angeles, titled The Frozen Lake, airs Tuesday, November 26 at 9/8c on CBS.