The premise of the show was that an aunt named Harriet has a trunk full of magic hats in her attic. When her young niece wears a hat from the trunk she is transported to a place related to the hat.
In the show's premise, Aunt Harriet possesses a trunk containing enchanted hats in her attic. Whenever her niece dons one of these hats, she is whisked away to an area associated with that particular hat.