What I think of this animates movie. This does give away a little of the movie but not the main story.

When a little girl gets lost in Jellystone, can Yogi and Boo Boo help find her? and why is someone so interested in Jellystones lake?

I got this idea from Hucklebarry hound in Behind the Laughter from the Shimpson's show and Yogi and the Magical Flight Of The Spruce Goose.

a new bear named Lilly comes to live in Jellystone, and Boo Boo immediatley likes her. everything starts off fine, but trouble brews when two rough men come to Jellystone looking for a runaway bear...