Newt Scamander, the protagonist in Fantastic Beasts and Where to Find Them, made a mysterious blink-and-you-miss cameo in the Prisoner Of Azkaban movie that left all Potterheads baffled. He was shown only for a few moments as a name tag moving about in the Marauder's Map. Seeing as he was born in 1897, Newt was probably in his nineties when the events of Prizoner of Azkaban were underway. It might have been just an Easter egg for enthusiastic Potterheads, but I think it had a greater influence. Let's look into some reasons which might have driven him to a brief Hogwarts' visit.
To Study The Dead Basilisk
A complete enthusiast of magical creatures, Newt probably couldn't stop himself from giving in to the temptation of seeing a dead Basilisk. A basilisk is a very dangerous and extremely rare creature as mentioned in the Most Macabre Monstrosities book:
"Of the many fearsome beasts and monsters that roam our land, there is none more curious or more deadly than the Basilisk, known also as the King of Serpents. This snake, which may reach gigantic size, and live many hundreds of years, is born from a chicken's egg, hatched beneath a toad. Its methods of killing are most wondrous, for aside from its deadly and venomous fangs, the Basilisk has a murderous stare, and all who are fixed with the beam of its eye shall suffer instant death. Spiders flee before the Basilisk, for it is their mortal enemy, and the Basilisk flees only from the crowing of the rooster, which is fatal to it."
There probably had been only one in the whole wizarding world and Newt couldn't miss this opportunity to see a Basilisk with his own eyes (he couldn't hope to see one alive since that can result in imminent death). Hence, he might have been off to Hogwarts to seek Dumbledore's permission to see the beast. Dumbledore, who had once fought for Newt against his expulsion, wouldn't have denied his request. So, it's quite a plausible possibility.
To Meet Hagrid And Explore The Forbidden Forest
We shouldn't forget that Newt wasn't the only one who had a strong affinity towards magical creatures. Rubeus Hagrid, gamekeeper at Hogwarts, shared the same interest. It was his love for magical creatures which earned him the position of Professor of the Care of Magical Creatures. Newt probably wanted to meet with Hagrid and discuss these magical beings with him.
In addition to that, Newt could have wanted to explore the Forbidden Forest and the creatures living in it. Hagrid knew more about the forest than any other wizard or witch (except maybe Dumbledore). So, Hagrid could have served as a guide if Newt wanted to go exploring.
To Talk About Ariana Being An Obscurial
There have been many fan theories claiming that Ariana was an Obscurial. Ariana was victim to 'sudden outbursts' which had inadvertently led to the death of her mother and quite possibly herself.
"It destroyed her, what they did: She was never right again. She wouldn't use magic, but she couldn't get rid of it; it turned inward and drove her mad, it exploded out of her when she couldn't control it, and at times she was strange and dangerous. But mostly she was sweet and scared and harmless."
Newt was experienced when it came to dealing with Obscurials, he even had one contained in his suitcase. He succeeded in extracting the destructive force from a young girl in Sudan, as he recounted in the #FantasticBeasts movie.
Dumbledore was heartbroken and filled with remorse when Ariana was accidentally killed midway of a three-way duel involving Grindelwald, Aberforth and Albus himself. He continued to blame himself for his sister's demise. Later, however, he might have considered the possibility of Ariana being an Obscurial and could have summoned Newt in order to clear his doubts, as there was no one who possessed better knowledge on Obscurials than him.
To Suggest Using Buckbeak To Save Sirius
Could Newt have been the one who came up with the brilliant plan of helping Sirius to flee on Buckbeak? Sirius and Buckbeak were saved from imminent death by virtue of Hermione's Time Turner and Dumbledore's brilliance, but it could have been Newt who actually came up with the plan. Newt's mother was a breeder of Hippogriffs, which ignited his interest in magical creatures at an early age. That could have been why he suggested using Buckbeak as an escape route for Sirius. Sirius was locked up in Flitwick's office in the seventh floor waiting for the Dementor's kiss and there was no other way to flee. Buckbeak was the only plausible option for his escape. So Dumbledore, inspired by Newt's idea, urged Hermione to use the Time Turner and save two innocent lives at once.
"Sirius is locked in Professor Flitwick’s office on the seventh floor. Thirteenth window from the right of the West Tower. If all goes well, you will be able to save more than one innocent life tonight. But remember this, both of you. You must not be seen. Miss Granger, you know the law — you know what is at stake... you — must — not — be — seen."
To Pay Dumbledore A Visit
Amidst all these speculations, the most obvious one would be that Newt had been just paying Dumbledore a visit for old times' sake. Dumbledore had been Newt's Transfiguration teacher when he attended Hogwarts, and he even stood up against Newt's expulsion when he was accused of a crime he didn't commit. That still couldn't stop his expulsion and Newt had to leave Hogwarts. So, it could have been out of respect for Dumbledore that Newt paid him a visit in his frail, old state. Also, we know that the foreword to Newt's Fantastic Beasts and Where to Find Them book was actually written by Dumbledore. So Newt could have very well approached Dumbledore regarding the foreword to his book.
Newt's appearance in the Marauder's Map could have triggered a whole lot of events in the Harry Potter universe, and his involvement with Dumbledore could have further increased his importance in the Fantastic Beasts series. Ultimately, the reasons for his mysterious appearance are still unknown. For fans out there who think that the reasons would be unveiled in the sequels to the Fantastic Beasts series, I would say that it is highly improbable. The time gap between these two events is quite big and there is no way the producers are going to divert from the main plot to explain the reason for his brief appearance, but it's still fun to speculate.
Why do you think Newt visited Hogwarts in Prisoner of Azkaban? Leave your thoughts in the comments section below!