The phenomenon references the intersection of a popular fantasy book and film series with a national holiday tradition, typically involving retail opportunities. Specifically, it involves themed merchandise available at a chain of seasonal pop-up stores. An example includes the sale of Hogwarts robes, wands replicating those used by characters in the stories, and related decorative items during the months leading up to October 31st.
The significance lies in the convergence of a globally recognized brand with a cultural event focused on costuming and themed celebrations. This generates substantial revenue for both the intellectual property owner and the retailer, capitalizing on pre-existing fan loyalty and the demand for unique costume options. The historical context includes the continuous expansion of the Harry Potter franchise beyond books and films into various forms of consumer products, and the increasing popularity of elaborate, character-based costumes for Halloween.