Gibb's rule no. 12: Never date a coworker.
The character Anthony DiNozzo performs an imitation of the comic book character Hulk/Bruce Banner and describes him as a "big dumb oaf", In the comics, Banner is a brilliant scientist who is suffering from multiple personality disorder. Banner has displayed many different personalities over the decades, and some of these Hulks are intelligent and articulate.
Although not a major plot item, this is part 2 of the Port to Port Killer Arc.