It took more than 50 years, but this week, Mary Poppins will finally get a sequel. Mary Poppins Returns promises to re-immerse families in the colorful, musical world of the world’s best nanny. There will be more dancing, more singing, and more animated penguins. But will it answer the longstanding questions about what Mary is and why she can fly?

Fans have been speculating about the source of Mary’s abilities, her relationship with Bert, and the identity of Andrew the dog for decades—and they’ve produced some truly inspired conspiracy theories along the way. Here are 10 theories that are either just wild enough to work, or just plain wild.

1. MARY POPPINS STUDIED AT HOGWARTS.

What explains Mary’s bottomless carpet bag? Or her ability to fly with an umbrella? It can only be magic, and where do people learn how to cast spells? At the Hogwarts School of Witchcraft and Wizardry, of course. Multiple Reddit threads contend that Mary Poppins was a student there—either a Hufflepuff or a Ravenclaw—around the same time as Albus Dumbledore. From there, she studied Muggles in the field, posing as a nanny to learn more and identify gifted children. As for evidence supporting this claim, many of Mary’s enchanted accessories appear in the Harry Potter universe, from her bag (similar to Hermione’s in Deathly Hallows) to her magical mirror (Mirror of Erised, anyone?).

2. SHE’S A TIME LORD.

Another popular fan theory maintains that Mary Poppins is a Time Lord from Doctor Who, and Bert is her former companion. There’s her carpet bag, which is bigger on the inside. Then there’s her umbrella, which Redditors argue is an “amalgamation of her TARDIS and sonic screwdriver.” Mary feels compelled to help people but disappears when the job is done, barely saying goodbye.

3. SHE WAS BERT’S NANNY.

In “Supercalifragilisticexpialidocious,” Bert sings that he was “afraid to speak” as a child, until he heard the nonsensical word that changed everything. But where did he learn “supercalifragilisticexpialidocious”? Some fans suggest that Mary taught it to him when he was young—because she was his nanny. Bert is weirdly comfortable with her magic, and finds joy in the dullest jobs, just as Mary teaches the children to find the fun in chores. On top of all that, the dancing penguins seem incredibly familiar with Bert, perhaps because he has been visiting their universe for decades. The jury may be out on this one, but Emily Blunt buys it.

4. BERT AND MARY WERE MARRIED.

Alright, maybe she wasn’t Bert’s nanny. But could Mary Poppins have been Bert's wife? The theory goes that Bert and Mary were happily married, and desperately wanted children. Only Mary had trouble conceiving. Then she got sick. Bert picked up more and more odd jobs to pay her medical bills, but Mary passed away. She later returned as some kind of otherworldly being, working as a nanny to experience the motherhood she missed out on in life. But she eventually realized she’s not Jane or Michael’s mother and decided to move on, giving Bert some closure before she left for good.

5. EVERYONE IS ON DRUGS.

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Mary Poppins might seem bright and cheery, but one theory insists it’s actually a metaphor for drug addiction. Cracked has a whole five-point case, starting with Mary’s frequent pleas for time off and checkered work history. (Bert has an even harder time keeping a job.) She’s also prone to mood swings and spends a whole day in a two-dimensional world full of cartoons. Oh, and what’s the deal with Uncle Albert?

6. BERT IS RELATED TO MR. BANKS’S BOSS.

Dick Van Dyke is the only actor in Mary Poppins with dual onscreen roles. In addition to Bert, he plays the wizened Mr. Dawes, Sr., who runs the bank where Mr. Banks works. Fans on Reddit claim this is no coincidence. The elder Mr. Dawes is supposed to look like Bert, because he’s his father. (Or maybe his grandfather?) Among other things, it would explain why Bert’s Cockney accent is so bad. That’s not how he talks—that’s just a rich kid putting on an act.

7. MARY IS A GREEK GODDESS.

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Did Mary descend from Mount Olympus? Multiple theories suggest she’s Hestia, the Greek goddess of the hearth, on a mission to bring peace back to the Banks's home. It would explain her magical powers, as well as her vanity in the presence of mere mortals.

8. MARY IS ACTUALLY JUST GOD.

This theory rests entirely on the comic book series The League of Extraordinary Gentlemen, which features a mysterious cloaked figure in its third volume. She emerges from the sky, carries a bag and umbrella, and speaks of her “concern for children.” But most importantly: she’s the only being powerful enough to take down an Antichrist. Here, Mary Poppins is a manifestation of God, a fact she underlines by mentioning her appearance on “every page” of the Bible.

9. Mary is an evil witch intent on killing the kids.

Not all witches are nice. Some Redditors believe that Mary is the mean kind of witch, one that torments kids for kicks—or sedates them with a “spoonful of sugar” so she can chop them up for potion ingredients.

10. ANDREW THE DOG IS MAUI from moana.

Before Mary Poppins even arrives, at least a dozen nannies respond to Mr. Banks’s advertisement. But a mysterious gust of wind blows them all away—and one Disney theorist claims a Moana character is responsible. That’s right: Maui, demigod of the wind and sea, orchestrated the whole thing so Mary would get the job. But where was he in the scene? Since Maui is a shapeshifter, the theory goes, he took the form of the Banks's family dog Andrew, who remains firmly on the ground as the wind picks up.