The poster for Finding Nemo, the latest animated feature from Pixar, references the "3.7 trillion fish" in the ocean, then, in fine print, suggests that the number might be a conservative estimate. Whatever the true tally is, Finding Nemo gives the sense that if it weren't limited by its borders, it would eventually reveal them all. But never mind Pixar's characteristically impressive visual accomplishments. Given the steady advance of technology, it's not that much of a surprise that the studio can match its past efforts even while attempting more daunting scenarios with each film. (Here, most of the action takes place underwater, with all the shimmering currents and play between light and shadow that the setting demands.) What's more impressive, and in the end more important, is the high standard of storytelling that Pixar continues to meet by locating both humor and emotional depth in worlds created out of lines of code. Finding Nemo has to live up to that standard, if it wants to work at all after an opening scene that rivals Bambi for efficiently establishing nature's fury. Left a fretful single father, a clownfish named Marlin (voiced by Albert Brooks) cares cautiously for his only child. He leaves his anemone home with great trepidation, and–as everyone he meets notes, disappointedly–for a clownfish, he isn't particularly funny. But he is comedic and heartfelt, and, by necessity, courageous. After his son Nemo (Alexander Gould) is captured by a scuba-diving dentist with a yen for tropical aquariums, Brooks sets out for the mysterious land of Sydney, Australia, to bring him back. Between them, father and son encounter 12-stepping sharks, laid-back turtles, a helpful fish with a limited capacity to generate short-term memories (sweetly voiced by Ellen DeGeneres), a crusty aquarium veteran with the voice of Willem Dafoe, and other assorted wonders of the sea, all vividly three-dimensional, both visually and otherwise. The production team, led this time by writer-director Andrew Stanton, joins a silent comedian's sense of timing to a cartoonist's skill at emotional shorthand, alternating wild comic setpieces with introspective moments, and occasionally letting the two play out simultaneously. Like Pixar's previous films, Finding Nemo mines humor from the oddities of an unknown world but stays grounded in a familiar one, finding recognizable elements of heartbreak and happiness amid the ink-jetting octopi and irritable flounders.