Up to No Good

Often Harry Potter books (and their movies) are named after the magical artifact found within them. Up to this point, we had "the Sorcerer's Stone" and "Chamber of Secrets," but this time, J.K. Rowling shook things up by naming the book after Sirius. He may be a dog sometimes, but he's not an artifact.

Harry Potter and the Marauder's Map wouldn't be a half-bad title, but the map itself doesn't factor too much in the movie. Harry's dragged aside by the Weasley twins and presented with the Map, which displays the following text:

HARRY: "Messrs. Moony, Wormtail, Padfoot and Prongs are proud to present the Marauder's Map."

In the novel, Harry eventually learns that these four marauders were Lupin (Moony because of the moon), Pettigrew (Wormtail because he's a gross rat with a nasty tail), Sirius (Padfoot because of the pads on his puppy feet) and James Potter (Prongs because his Patronus is a stag).

But in the film, we're left to infer this. Harry uses the map to find Peter Pettigrew and insult Snape, and Lupin's clearly is familiar with the map, because he knows the key phrase to turn it back into a blank piece of parchment:

LUPIN: "Mischief managed."

Perhaps because he knew fans might feel shortchanged at the lack of map action, Cuarón fashions the end credits of the film as a dynamic, moving Marauder's Map. And if you sit through the whole credits, you won't be treated to a glimpse of the next Marvel film, but you will hear Harry say, "Mischief managed," as the screen fades to black.

For Harry fans at the time, this movie would have to be just enough mischief to tide them over until the next time Potter's up to no good.