The three flashback sequences are the first adaptations of original A.A. Milne stories since The Many Adventures of Winnie the Pooh and Winnie the Pooh and a Day for Eeyore. Edited to make Piglet the hero of the stories and to conform to the characters' idiosyncrasies as Disney has portrayed them, they nevertheless retain much of Milne's original plot. In this movie, Pooh changes the name of Pooh Corner to Pooh and Piglet Corner, something that he was originally going to do, but the name did not sound small or much like a corner, which was in fact what it was. Besides the Carly Simon songs, Sherman Brothers music is also featured.
The film's plot is based primarily on five A. A. Milne stories: "In which Kanga and Baby Roo Come to the Forest, and Piglet Has a Bath (Chapter VII of Winnie the Pooh), "In which Piglet meets a Heffalump" (Chapter V from Winnie-the-Pooh) "In which a search is organized and Piglet nearly meets the Heffalump again" (Chapter III from The House at Pooh Corner), "In which Christopher Robin Leads an Expedition to the North Pole (Chapter VIII of Winnie the Pooh) and In which a house is built at Pooh Corner for Eeyore (Chapter I from The House at Pooh Corner).
In the Hundred Acre Wood, Eeyore (Peter Cullen), Rabbit (Ken Sansom), Tigger (Jim Cummings), and Pooh (Jim Cummings) are working on a plan to extract honey from a beehive. The plan involves getting the bees to convey to a new hive by convincing them that Eeyore is a bee. Piglet (John Fiedler) comes up to them during the attempt, but is effectively told that he is too small to help. The plan goes awry when the bees do not fall for it, but Piglet manages to divert the bees into the new hive using a funnel and then seals the hive shut, trapping the bees.
However, no one has realized what Piglet had done to help out with the plan, having Piglet feeling uncared for; Piglet sadly wanders away. Eventually, Eeyore, Pooh, Rabbit, and Tigger notice that Piglet is missing, assuming that he has been scared off by the bees, and decide to find him. They are joined by Roo (Nikita Hopkins), and together the five friends search for Piglet. The search party is aided by Piglets' scrapbook, in which he has drawn pictures of the adventures that he has shared with his friends. The characters use the pictures to tell the stories depicted therein.
One of the stories told is the expedition to find the North Pole, where Piglet uses a long stick to save Roo (who has fallen in the river). His heroism is overlooked when he gives the stick to Pooh and tries to catch Roo, who has been catapulted into the air during the rescue attempt. Christopher Robin (Tom Wheatley) arrives as Roo is caught by Kanga (Kath Soucie) and then credits Pooh with finding the North Pole (the stick he is holding in his paws). Back in the present, the friends regret not sharing the praise with Piglet.
A second story told is the building of The House at Pooh Corner. Here Piglet comes up with the idea to build Eeyore a house and he and Pooh are joined by Tigger to build it. Tigger and Pooh do most of the work, whilst Piglet, unintentionally, gets in the way. The final house, however, is a disaster, but Tigger and Pooh go off to tell Eeyore about the house. Unfortunately, the house is being held together by Piglet, who eventually loses his grip and the house collapses. Tigger and Pooh go to inform Eeyore of the bad news, but Piglet arrives to tell them all that the house is fine. It is revealed that he rebuilt the house himself, but the location remains as Pooh Corner, since Pooh "would call it 'Pooh and Piglet Corner', if 'Pooh Corner' didn't sound better, which it does, being smaller and more like a corner".
Back in the present, an argument between Rabbit and Tigger ends with the scrapbook falling apart and then falling into the river. Without their guide, the friends return to Piglets house and, after a time, start to draw new pictures of Piglet and his adventures, some of which are new. Then, the friends again resolve to find their missing Piglet and go back out to find him. They come across several pictures from the scrapbook, which have floated downstream and then find the books bindings, suspended on a broken hollow old log, overhanging a raging waterfall. Pooh goes to retrieve it, but falls into a hole in the log. The others try to reach him, but the rescue attempt is just too short. Just as they ask who can help, Piglet arrives and attempts to help haul Pooh to safety, just as the log begins to collapse.
Eeyore, Rabbit, Roo and Tigger now stand by the edge of the ravine, next to the waterfall, but the log inside which Pooh and Piglet were trapped has fallen far into the waters below. The survivors begin to cry but are soon joined by a sad-looking Pooh and Piglet, who have managed to escape. Happy, the friends take Piglet to show him their new drawings, including a large one of Piglet dressed as a knight in shining armor. The next day they hold a party, but Pooh interrupts, taking Piglet to Eeyores' house, where he has changed the sign to read "Pooh and Piglet Corner"; "the least [they] could do for a little Piglet, who has done such big things!".
During the closing credits, Carly Simon reprises the song A Few Good Friends, which originally appeared during the scene showing the building of the House at Pooh (and Piglet) Corner, before it ends with the music from the rest of the film.
Piglet's Big Movie opened on its opening weekend at #7, earning $6 million. The
film domestically grossed $23,103,423—half the amount of what The Tigger Movie earned, but $39,767,123 overseas for a total of $62,870,546 worldwide, making it a moderate Box Office Success.
The film received generally positive reviews. Film critic Stephen Holden of New York Times called the film an "oasis of gentleness and wit." Nancy Churnin of The Dallas Morning News stated that Piglet's Big Movie was "one of the nifty pleasures in the process", despite her belief that "Disney may be milking its classics." Rotten Tomotoes has a 72% rating for critics, calling it "Wholesome and charming entertainment for young children.". The viewers rated it 65%.
In 2003 Disney released Piglet's Big Game for the PlayStation 2, Nintendo GameCube and Game Boy Advance as well as a CD-ROM game which was also entitled Piglet's Big Game. The latter is by Encore and Disney Interactive (Hulabee Entertainment for the CD-ROM version.) and involves helping Piglet assist in the preparation for a "Very Large Soup Party."
In their review, Edutaining Kids praised various features including the adventure/exploration aspect (the game is linear instead of using a main screen) and many of the activities (such as the color mixing, which they said offers an incredible variety of hues), but noted that it is much too brief and that Kanga and Roo are absent.