This movie starts when, atop the roof of an observatory at their cloud-filled home of Care-a-lot, the Care Bears hear Wish Bear's story of how she (as a Cub) found her new friend, a wishing star named Twinkers. The Care Bears are touched by this tale, but are a bit worried when she uses Twinkers' inherent power to wish them all some popcorn. Cheer Bear raises concern that this may be a frivolous use of Twinkers' power. Wish Bear, however, assures everyone that she is a trained professional.
The next day, Wish Bear uses the wishing power to help her friends. She wishes for plenty of rainbow sap for Share Bear, and for Grumpy Bear's rocket to have "zoom", but the wishes backfire when the sap overflows and the rocket spins out of control.
A monthly meeting of Care-a-lot's steering committee (with Champ Bear presiding) reveals a problem with the Caring Meter. The machine, which measures how much caring there is in Care-a-lot, has moved towards the raincloud side. Wish Bear suggests using her wishes, but is rejected since not all of them work as intended; they didn't like their wishes ("I Wish"). Disappointed, she decides to wish for other bears who like wishing as much as she does. This causes three new bears to arrive in Care-a-lot: Me Bear, Messy Bear, and Too Loud Bear.
Everyone is pleased to welcome the new neighbours at first, but things soon get out of control. The new bears unwittingly make a huge mess of everything (especially when the huge mansion they asked for causes pollution). Then, after a confrontation with them at a picnic ("Get a Lot") Wish Bear accidentally wishes Twinkers away to the new bears; they soon abuse the star's power with an amusement park focusing on Me Bear, a mud pie for Messy Bear, and a huge noisy motorcycle for Too Loud Bear. Once the new bears finally realise their problem, they try to fix it with more wishes, but to no avail—Care-a-lot becomes a blank white space (wishing that all of this was gone), the bears begin to glow in color (wishing for everything to be back how it was, but with more color), Grumpy Bear turns black and white (wishing for less color), and Messy Bear turns into Messy Cub (wishing for everything to be like it used to be). When they try to wish Twinkers back to Wish Bear, the star ultimately loses his power from exhaustion (because they had been pushing him much too hard). Wish Bear uses Grumpy Bear's rocket to bring him to the Big Wish, a grandmother star, in the sky. Big Wish restores his power, but not before Wish Bear assures her that she has learned her lesson, which is wishing is fun, but it is far more important to work hard to achieve your dreams.
Wish Bear tells them that wishes are not an effective solution any more, and everyone works together to make their home beautiful again ("It Takes You and Me"). At the end, Me Bear, Messy Bear, and Too Loud Bear, having seen the error of their ways, apologize and ask if they can still live in Care-a-lot. The rest of the bears agree and decide to go on a road trip.
As with 2004's Journey to Joke-a-lot, The Care Bears' Big Wish Movie was self-financed by the Nelvana studios in Toronto, Ontario. The second computer-animated production with the Care Bears, it is also the franchise's fifth feature instalment. Director Larry Jacobs had previously worked on another Nelvana venture, a public television series entitled Cyberchase. Mike Fallows, the director of Joke-a-lot, served as the supervising director. The film featured various voices from Joke-a-lot, among them Stephanie Beard, Julie Lemieux, Stevie Vallance, Robert Tinkler, Andrew Sabiston and Scott McCord. Animation was handled by Nelvana in Canada, and Crest Animation Productions in India. Big Wish marked the last time Nelvana embarked on a Care Bears project; from 2006 onward, the California-based SD Entertainment was responsible for future animated fare with these characters, starting with Oopsy Does It! in 2007.
The Care Bears' Big Wish Movie first aired on Canadian television on October 3, 2005; in the United States, it premiered on cable television's Disney Channel on October 17 and on ABC Family on December 23. The day after the U.S. premiere, it became one of Lions Gate Home Entertainment's five direct-to-DVD "marquee" offerings for young viewers; restaurant chain Burger King served as the promotional partner. Twice during 2005, Stephanie Beard (the voice of Wish Bear) promoted the film in the Toronto Star under the alias Suga Baybee; in October, she proclaimed that it "is going to be a classic". The film charted on Video Business' Top Kids Rentals list for January 23, 2006, where it ranked 20th. On August 11, 2007, it placed seventh on Billboard's Top Kid DVD Sales chart. Jeffrey Alan Schechter, the film's writer, was nominated for a Writers Guild of Canada Award. The film is known under two French-language titles: À vos souhaits les Calinours ! (in Canada's Quebec province) and De Nouveaux Arrivants chez les Bisounours (in France).
Days before the release of the Big Wish Movie, Scholastic Press published a Care Bears storybook based on the film; it was written by Sonia Sander and illustrated by Jay Johnson. One scene in the book involves Wish Bear and the three new Bears grocery shopping; this does not appear in the film. Later in the book, when Messy Bear wishes for everything to be like it used to be, it causes the Bears to travel back to the age of the dinosaurs; in the film, Twinkers just turns Messy Bear into Messy Cub.
Bruce Kluger of Parenting magazine referred to the Big Wish Movie as "Cute stuff, if a tad sticky-sweet: Heart-shaped toothbrushes, toasters, and waffles abound." Cristina Rouvalis of the Pittsburgh Post-Gazette gave it three stars out of four, and said that "Young Care Bear fanatics will wish for more." In April 2010's Journal of Aging Studies, Sylvia Henneberg commented that Big Wish, the grandmother star, served as "a poor substitute for a truly three-dimensional maternal figure".
The music for the Big Wish Movie was composed by Ian Thomas (also from Journey to Joke-a-lot), and conducted and orchestrated by Peter Cardinali. At his studio, Thomas worked with the Hamilton Children's Choir on the film's opening theme. In February 2005, Stephanie Beard said that "I Wish", a track she performed, "is my favourite cartoon song yet. It's so cute; I can't wait for the world to hear it."