The world isn't big enough for one Tony DiNozzo. Put two together and it's just off the hook.
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Tony and Ziva go undercover on NCIS. Tony Sr., that is.
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Abby in a photo from the November 9, 2010 episode of NCIS. "Broken Arrow" also marks the return of Tony Sr.
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NCIS Season 8 Episode 7 Quotes

(to McGee) This is surreal. I feel like I'm in a James Bond movie directed by Fellini. On a stakeout, watching my father and Ziva go undercover, while you munch on a Nutter Butter.

Tony

Admiral Chase: Does Agent David carry a weapon?
Gibbs: She is a weapon.