This week’s Wizarding World Book Club theme is Secrets and Concealment – something the Marauders certainly knew a thing or two about.

Prongs, Padfoot, Moony and Wormtail in their transfigured animal forms.
© JKR/Pottermore Ltd. ™ Warner Bros.

The first time we hear of the Marauders – or at least, the first time we hear the boys that were the Marauders described as such – is when Fred and George gift Harry their spectacular map. It’s a magical work of art, with its detailed illustrations of Hogwarts and microscopic dots that represent actual people.

But the Marauders did more than induct Harry into their world of mischief – we learned some valuable lessons from Messrs Moony, Wormtail, Padfoot and Prongs…

Hogwarts has secret passageways

…starting, of course, with the seven hidden passages on the Marauder’s Map. With most of them leading into Hogsmeade, the map becomes invaluable to Harry as a means to join his fellow third-years on their weekend trips. Without the Marauder’s Map Harry wouldn’t have access to Zonko’s or Honeydukes or the Three Broomsticks – not to mention the help it gave Fred and George. It’s a piece of mischief-making genius.

How to cast a Patronus

When Harry starts Anti-Dementor lessons with Lupin, he doesn't know his teacher is actually Moony, or that Lupin is a werewolf. He does, however, know Lupin is the best Defence Against the Dark Arts teacher he’s ever had, as demonstrated when he shows Harry how to cast a Patronus. This is advanced magic. It takes a lot of practice, chocolate and coming to terms with hearing his parents’ voices, but Harry gets it eventually, thanks to Lupin’s patience.

Harry's stag patronus charges across the lake towards the Dementors.
© JKR/Pottermore Ltd. ™ Warner Bros.

Snape had troubled schooldays

When Moony, Wormtail, Padfoot and Prongs insult Snape via the medium of parchment, it’s obvious his history with the Marauders is not a positive one. The depth of Snape’s animosity is revealed when he discovers Sirius, aka Padfoot, in the Shrieking Shack. Snape is so desperate for vengeance for the Marauders’ nasty schoolboy pranks that he ties up Lupin, threatens Sirius with the Dementor’s Kiss, and ends up knocked out by the collective force of Harry, Ron and Hermione.

Not all Animagi are registered

The Ministry of Magic keeps tabs on Animagi – wizards that can turn into animals – and the process of becoming an Animagus is extremely long and difficult. That much we know from Hermione, who is nothing if not thorough. But, Lupin tells us, it is possible to become an Animagus without the Ministry knowing, although perhaps not advisable. It took three years for Padfoot (Sirius), Prongs (James) and Wormtail (Peter Pettigrew) to become Animagi and while it may have made for a better school experience for Lupin, the dangers are clear when you consider the actions of unregistered Animagus Peter Pettigrew.

Remus and Sirius fight as werewolf and dog.
© JKR/Pottermore Ltd. ™ Warner Bros.

The story behind the Shrieking Shack

Lupin’s monthly transformations happened in the Hogsmeade building christened the Shrieking Shack. Becoming a werewolf was so painful and violent for Lupin, shut away so he couldn’t hurt anyone, that he would howl and scream. The noise was loud enough that those who heard it put it down to violent spirits, and so the legend of the haunted Shrieking Shack was born.

What really happened when Harry’s parents died

When Harry discovers his parents were murdered after their Secret-Keeper betrayed them to Voldemort, he – like those around him – believes the culprit is his father’s old friend Sirius. But in the Shrieking Shack he learns it was Peter Pettigrew. The Potters chose Peter as their Secret-Keeper and in return he sold them to Voldemort. Then, when Voldemort was defeated, Peter faked his own death, landed Sirius in Azkaban, transformed into a rat and hid in the sewers. What a guy.

The truth about Scabbers

Ron’s family rat, Scabbers, was always a bit of a puzzle. Too old to be a normal rat but showing no magical signs, his only moment of glory was biting Goyle’s hand onboard the Hogwarts Express. Not a particularly illustrious career for a wizarding pet. On the other hand, Hermione’s Crookshanks is suspicious of Scabbers from the start and is proved completely right when it turns out Scabbers is actually the traitorous Pettigrew.

Peter Pettigrew revealed as Scabbers
© JKR/Pottermore Ltd. ™ Warner Bros.

How to escape from Azkaban

That Sirius managed to escape the supposedly impenetrable Azkaban is such a feat even the Muggle Prime Minister has to be informed. Yet when Sirius tells Hermione how he did it, he’s not sure – although being an Animagus was essential. If you want to slip past a Dementor, it seems, you just need to have an obsessional thought that is neither happy or sad and the ability to turn into an animal with less complex emotions. Easy.

What Sirius is to Harry

The best thing we learn from the Marauders is how close they were (well, okay, not Pettigrew) and that Sirius – best man at the Potters’ wedding – is Harry’s godfather. There is one bright, brilliant moment when it seems Harry might be able to live with a sort-of family member who actually likes him. It’s not to be, sadly, but at least Harry gains someone who cares.

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