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The casts of NCIS: Los Angeles and Hawaii Five-O are teaming up for a special, two-episode crossover event! Get an exclusive first look...

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In the first episode of the two-night special event – on Hawaii Five-O, airing Monday, April 30 on CBS -- Callen and Sam (Chris O'Donnell and LL Cool J) team up with Danny and Chin Ho (Scott Caan and Daniel Dae Kim) in Hawaii to track down a suspect who is threatening to release a deadly virus into the population.

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The action concludes Tuesday, May 1 on NCIS: Los Angeles, when Callen, Sam, Danny and Chin Ho travel to the mainland on the heels of a suspect to stop the deadly virus -- and prevent a global pandemic.