Can the 'NCIS: LA' Team Stop a Potential Outbreak? (PHOTOS)

Meredith Jacobs

NCIS: Los Angeles is traveling back to the USS Allegiance this season, but don't expect to see JAG's Harm (David James Elliott) again.

Sam (LL Cool J) and Callen (Chris O'Donnell) will be joined by a familiar face while they're on board: Ehsan Navid (Wesam Keesh), whom the team first met on a case in Season 5's "Allegiance." And he's since joined NCIS!

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These actors left quite the impression on the show and fans.

But it's not an entirely happy reunion in "Yellow Jack," given that while the agents are aboard the ship, it's placed under quarantine for a possible Ebola exposure. Back on dry land, Kensi (Daniela Ruah) and Deeks (Eric Christian Olsen) investigate the murder of a petty offer who recently left the USS Allegiance and is linked to the Ebola exposure.

Click through the gallery above to see who wears the Hazmat suit the best and a look at the team's investigation.

NCIS: Los Angeles, Sundays, 9/8c, CBS