When the girls discover that their parents have mistakenly taken embarrassing home movies to an awards banquet, they join forces in order to save face. Their cross-island trip turns into a race against time in order to beat their parents to the podium and stop the world from seeing them at bath time.

The Thornberrys meet the Fensterkopfs who make false documentaries. The Fensterkopfs' kid lies to Eliza and gets them all stuck on a cliff. After the families barely escape an avalanche, the value of truth is learned by all.