''Let me explain it for the readers, because I'm pretty smart,'' says ''School of Rock'''s Jack Black. ''Not only does 'Shark Tale' mean 'shark story,' it also means, like, the back end of a shark. Like 'shark tail.' See?'' Gotcha. Actually, once upon a time, this computer-created cartoon confection -- the latest from Shrek distributor DreamWorks, and the first produced by the studio's Southern California animation unit -- went by the more menacing moniker ''Sharkslayer.'' But during ''Shark Tale'''s three-year development swim, the film evolved, thanks in large part to the comic casting of Will Smith and Black. The ''I, Robot'' action hero plays Oscar, a little fish whose big mouth gets him in trouble with mobbed-up great whites, led by Don Lino (Robert De Niro, naturally). Oscar finds a buddy in Don Lino's son, Lenny (Black), who not only has no appetite for ''the life''...but he's also a vegetarian. ''In the beginning,'' says producer Bill Damaschke, ''we set out to make a movie a little more noir, perhaps a little darker than where we've landed.''
Indeed, stuffed to the gills with jokey Mafia movie references, ''Shark Tale'' sports less naturalistic 3-D animation than, oh, say, ''Finding Nemo'' (from DreamWorks archenemies Disney and Pixar). While both films were produced concurrently, Damaschke says, ''The only thing they have in common is that they both take place underwater.''
''Shark Tale'' is ''very contemporary. Our reef is a fantasy underwater version of New York or Chicago. If you've seen our character design, our actors have crept very purposely into their alter egos.'' Case in point: Martin Scorsese's Sykes, a blowhard puffer fish. ''I'm not really acting. It's me. The fish even has big eyebrows!'' says the director, who improvised many of his scenes with longtime collaborator De Niro.
Black, meanwhile, praises the production for plying him with shrimp scampi burritos and rotisserie chicken during his nine vocal sessions (''I can't bring the rocket sauce without some fuel'') and says fans should expect some Tenacious D-lish riffs. ''There are some straight-up Jack Blackisms. I'll let you figure out which ones.''
WHAT'S AT STAKE For DreamWorks Animation, which has just filed to go public, a chance to reel in investor confidence.