The Dursleys Intro to Magic 101

The morning of the day that Harry needs to go get his supplies for Hogwarts, the Dursleys get an interesting letter inviting them to the student-family ball. Somehow Dudley convinces his parents to go, and they need to pick up robes, get on the train, and navigate the school as smoothly as possible.

Will they manage? What will happen when the Dursleys figure out everything that Harry has done to save the wizarding world, the muggle world, and everything as a whole?