LL Cool J, Chris O'Donnell

The deals are now done, and Chris O'Donnell and recording artist LL Cool J are on board for CBS' much-ballyhooed NCIS spinoff.

O'Donnell will play Callen, a chameleon-like lead agent, while LL's character, a former Navy SEAL, is described as hard on the outside but "thoughtful, eloquent and disarmingly charming" under the surface.

Previously announced castings include CSI alumna Louise Lombard (as the series' female lead, a military police major turned investigator), Peter Cambor (playing a quick-witted operational psychologist) and newcomer Daniela Ruah (as a young investigator specializing in forensics and criminology).

Created by NCIS boss Shane Brennan, the spinoff will air later this season as a two-part episode of NCIS.

Reports that the offshoot's title will be NCIS: Legend are unconfirmed at this time (to which I say, "Thank god. Sounds like a video game.")

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