Boo-Boo Bear wakes up from winter hibernation, excited about the new Spring. Then Yogi Bear wakes up, only interested in finding some food to eat. Cindy Bear unsuccessfully tries to woo Yogi. After Ranger Smith thwarts Yogi's latest attempts to grab some food, Yogi gets angry and convinces the Ranger to transfer him out of Jellystone National Park. Smith prepares Yogi to be sent to the San Diego Zoo along with an identification tag. Yogi first says goodbye to everything, but tricks another bear named Corn Pone into going to California in his place. Boo-Boo and Cindy are unaware of this, thinking Yogi has departed for good.
Soon, Yogi is stealing food from all over the park under the alter ego "The Brown Phantom". Smith believes "The Brown Phantom" is a mysterious bear-like vigilante whom the Park Commissioner hired to replace Yogi, and scares away all of the Jellystone goers and gobbles their food up shortly after stealing it. He threatens whoever it is to be sent to the zoo and comes up with a clever plan to stop "The Brown Phantom" and save the park, not knowing it is actually Yogi.
Cindy, wishing to be with Yogi at the zoo, angers Smith into mistakenly sending her away. However, she gets sent to the St. Louis Zoo by train instead, as the San Diego Zoo does not need any more bears. When she realizes her true destination, she gets very sad, crying since she knows she would be far from Yogi now. Late that night, Cindy falls out of the train and becomes lost. A traveling circus, run by the Chizzling Brothers, is looking for a great act to raise their ratings, when suddenly, their dog Mugger runs off and scares Cindy into walking on the telephone wires, the perfect act to save their circus.
Yogi has recently missed Boo-Boo and, above all, Cindy. On his way back to talk to Ranger Smith, Yogi finds that Cindy had gone missing on the way to the St. Louis zoo. Ranger Smith, wanting to send Yogi back to the San Diego zoo, is locked in a closet while Yogi and Boo-Boo escape from Jellystone to find Cindy. After an extensive travel, Yogi and Boo-Boo locate Cindy, who is being kept a prisoner, forced to perform her high-wire act for the Chizzling Brother's circus. As Yogi confronts the manager, Grifter Chizzing, he is tricked into joining Cindy in her cage, where Grifter tells him he's now in "show biz." Boo-Boo releases Yogi and Cindy and they make their exit.