If you’ve seen Shazam!and if you haven’t, you should stop reading right now—we're sure you have a lot of questions: Was that really Superman? Who on Earth were all those other superheroes? And what’s the deal with that mid-credits scene?!?

Well, we’re here to help answer that last and most vital question for you. That small talking worm is a classic Shazam villain named Mister Mind. If you were particularly eagle-eyed, you may have noticed him living in a glass jar within the Rock of Eternity near the beginning of the movie before he managed to escape and find his way into Sivana's prison cell at the very end of the film, ready to plot vengeance on Shazam!

Just like Billy Batson himself, the tiny green villain was originally introduced in the now defunct Fawcett Comics. Created by Otto Binder and C.C. Beck, he first appeared as a disembodied voice in 1943's Captain Marvel Adventures #22 before revealing his terrifying and ridiculous true form in Captain Marvel Adventures #26. Though his stature may be small, the power of Mister Mind comes from his hyper-intelligence, telepathic dominance and the organization which he establishes to throw his evil weight around...the Monster Society of Evil!

Not only does the Society have one of the best super-villain team names of all time, but they're particularly notable because they represent one of the first instances that a superhero had to face down a team made up of villains he already fought. (For other ways in which Shazam’s been a trendsetter, check out our list of Shazam Family firsts.) With the Monster Society of Evil behind him, Mister Mind quickly became one of Shazam's most famous Golden Age rogues, second only to Dr. Sivana. Throughout his history, he’s also been one of the most despicable, regularly teaming up with Nazis and even Hitler in his quest to destroy Billy Batson and take over the world.

Mister Mind’s pre-DC life as a part of Fawcett Comics centered heavily on the "Axis of Evil" and the wartime era in which he was created, but even though those influences came very directly from real-life horrors, he was one of the original surreal super-villains, whose unlikely appearance and strange powers were a spiritual precursor to creations like the Doom Patrol, Gorilla Grodd and Bat-Mite. Mister Mind’s influence can even be found within wider pop culture, with characters like SpongeBob SquarePants' evil mastermind Plankton being built in a similar mold.

Though Mister Mind's role in Shazam! may have seemed small, it hints at the wider world of Shazam and the possibilities for a potential Monster Society of Evil within the cinematic world of DC. That could take any number of forms, since over the decades, the Society has changed shape and membership time and time again, from thousands of evil-doers to a slimmed down group of bad guys, with Dr. Sivana often making an appearance alongside a strange series of real-life dictators and an odd assortment of shape-shifters, satyrs, sperm whales and synthetic animals.

And you thought the Rock of Eternity was strange!

Mister Mind eventually joined the DC Universe proper in All-Star Squadron #51, where he got a very strange origin story which saw him drawn to Earth-2 due to his fondness for World War II-era radio programming. But when he arrived, he discovered that his favorite character was fictional, so he decided to take over the world instead. The '70s were truly a wild, wild time.

The fact that Mister Mind has survived long enough to be a part of Shazam! speaks to the uniqueness and strength of the little guy as a character. He may be evil, but he’s a fun kind of evil, which is pretty rare in comics these days. Also, it should be mentioned that Shazam!’s mid-credits scene is actually very reminiscent of the final page (above) of Geoff Johns and Gary Frank’s 2013 Shazam! graphic novel, which is the comic from which much of Shazam!’s storyline was adapted. Johns’ series is now continuing, with a new issue #1 released a few months ago that picks up where his earlier series left off—and while Mister Mind and Dr. Sivana haven’t yet played a major role in the series, it’s clear they’re plotting something.

In short, if you’re curious about what Shazam!’s Mister Mind mid-credits scene may mean for a potential sequel, you could do worse than to check out the current Shazam! series. Just sayin’.

Could there be a frightening version of the Monster Society of Evil coming together in Billy Batson’s big screen future? It’s too early to know at this point, but let’s not forget, David F. Sandberg DOES have a history in horror. Mister Mind may seem non-threatening, or even laughable or cute. But with this longtime Shazam villain, things could get really dangerous and dark very quickly!

Shazam!, starring Zachary Levi, Asher Angel and Mark Strong, is now in theaters. To discover more about DC's latest movie, click here.

Rosie Knight writes about comics, movies and TV for DCComics.com and DCUniverse.com. Be sure to follow her on Twitter at @RosieMarx.