Yogi Bear.Yogi (Aykroyd) and Boo Boo (Timberlake) are two brown bears who like stealing picnic baskets from visitors to Jellystone Park, while park rangers Smith (Cavanagh) and Jones (Miller) try to prevent the thefts. Meanwhile, Mayor R. Brown (Daly) realizes that Franklin City is facing bankruptcy due to profligate spending on his part. Brown plots with his Chief of Staff (Corddry) to raise money for the town budget (and his upcoming gubernatorial campaign) by shutting down Jellystone Park and opening the land to logging. To save the park, Smith and his love interest Rachel hold a Centennial Festival and fireworks show in an attempt to sell season passes. To sabotage the effort, Brown promises Jones the position of head ranger if the funds are not raised. Yogi and Boo Boo had promised Smith to stay out of sight during the festival, but Jones convinces them otherwise. The bears try to please the crowd with a waterskiing performance, but Yogi inadvertently sets his cape on fire, causing fireworks to be launched into the crowd, who flee in panic. After Jellystone is shut down, Smith is forced to stay in Evergreen Park, a small urban enclave choked with litter and pollution. Seeing that their home is in danger of being destroyed, Yogi and Boo Boo travel to Evergreen Park, where they and Smith figure out Brown's plan. They all return to Jellystone with Rachel, where they learn that Boo Boo's pet turtle is a rare and endangered species known as a "Frog-Mouthed" turtle. The Chief of Staff learns about the turtle and, since the park cannot be destroyed if the turtle is living there because it would be home to an endangered species, sends Jones to kidnap it. On the day that Brown is planning a press conference to begin the destruction of the park, Smith, Rachel, and the bears rescue the turtle and try to bring it to the media's attention. Jones, learning that he had been manipulated by Mayor Brown, has a change of heart and helps the team bring the turtle to the press conference...