Blondie for a Moment

While looking through his collection of images for the Backgrounders website, UU discovered and passed on to me this pic from "Fair Enough." For one instant, as the scene shifts between Ms. Li and the class, the Jennifer on the left becomes a blonde. When the scene shifts to her again, she has black hair once more.

Animation errors. I love 'em.

Now try to explain them in the context of the show. That is the fun part. More after I wake up.