If you were immediately aware that that nonsensical seeming series of "duhs" was in fact the iconic intro music to the classic Harry Potter films, get ready to be so overwhelmed with joy you'll think you've been hit by a bludger: The official teaser trailer to HBO's Harry Potter 20th Anniversary: Return to Hogwarts is finally here!

This retrospective, which was announced back in November, will feature appearances from a lion's share of the unforgettable cast. Get ready to relive all of the magic again, and start combing through your mail to see if you got your Hogwarts letter (even though you're a fully grown adult, it's a British school for children, and the US postal worker who comes to your house is really tired of your constant heckling).

Of course, after seeing this teaser trailer, we will now also be going through our mail looking for an invitation to this reunion. We'd want any reason to re-enter the world of Hogwarts - If you don't want sidekicks like Hermione Granger and Ron Weasley, what are you doing with your life?

We would be honored to be even the sidekick to the sidekick of anyone at this event.The guest list, featured in the final moments of the trailer, is magically magnificent. The HBO Original will feature appearances from Daniel Radcliffe, Rupert Grint, Emma Watson, Helena Bonham Carter, Robbie Coltrane, Ralph Fiennes, Jason Isaacs, Gary Oldman, Imelda Staunton, Tom Felton, James Phelps, Oliver Phelps, Mark Williams, Bonnie Wright, Alfred Enoch, Matthew Lewis, Evanna Lynch and Ian Hart.

 Harry Potter and the Prisoner of Azkaban New York Premiere - Arrivals
(Photo : (Photo by Jim Spellman/WireImage))

We'll know more about this Fluffy-sized event as we get closer to the premiere date, but fans don't have to wait long at all: The Harry Potter 20th Anniversary: Return to Hogwarts comes out on HBO on January 1st.