Chubby fifth grader Tilla is the biggest in her class and is used to the others following her lead. She doesn't like Anne, the new girl in school, and turns most of their classmates against her.

The rivalry takes a nasty turn when Tilla destroys Anne's bike and Anne gets revenge by painting a mean picture of Tilla. It takes an emergency to teach these two very different girls how to work together.

Based on a children's book by Rosel Klein.