The famously disaster-prone Mildred, witch in training, flies in for a brand-new adventure that makes a perfect Halloween treat.

Mildred is starting her third year at Miss Cackle's Academy for Witches with high hopes of improving her klutzy record. But that's before a curling-iron catastrophe leads her to experiment with a hair-growing potion with hair-raising results. And it's before she raises the ire of Miss Granite, the odd new teacher who doesn't seem to act like a teacher at all. Could she be an imposter? And is there anything in Mildred's bag of tricks that can save the school if her hunch is right?