Oscar is the main protagonist of the 2004 DreamWorks animated film Shark Tale. He is a deluded, prideful, cool, street-talking rainbow tropical fish, who dreams of fame and fortune, and in order to achieve his goal, he fibs, saying that he slaughtered Frankie, the son of Don Lino and older brother of Lenny, which makes him the famous Sharkslayer.
He is voiced by Will Smith, who also plays Agent J in the Men in Black trilogy.