A great concept for this fanfic could be that the actors are on a movie set, but instead of filming, they accidentally step through a magical portal that leads them to a different time in the wizarding world. For example, they end up during the time of the Marauders. They might be mistaken for strange wizards at first. The actors would then have to navigate this new world, using their knowledge of the 'Harry Potter' story to their advantage. They could also introduce some Muggle technology to the wizards, like showing Sirius Black how a mobile phone works. This would create a lot of comical and interesting situations.
Well, perhaps in the fanfic, the 'Harry Potter' actors are cursed to forget their real identities and believe they are the characters they played. So, Rupert Grint would think he is Ron Weasley and start causing all sorts of chaos in the Muggle world as he tries to find his way back to Hogwarts. Or, the actors could be invited to a special event at Hogwarts and end up having to perform a play about the events of the wizarding war, which could lead to some really interesting interactions with the characters who lived through it.
One idea could be that the actors from the Harry Potter movies get magically transported into the wizarding world of Harry Potter. They could use their knowledge of the story to help the characters, or they could be completely bewildered and cause chaos. For example, Daniel Radcliffe could end up having to explain to Harry Potter himself how his story is told in the Muggle world.
A possible plot could involve a Dragonborn who discovers a hidden portal to the wizarding world. In the wizarding world, they learn about magic wands and spells. The Dragonborn could then combine their Thu'um powers with magic spells to fight against dark forces that are threatening both worlds. For example, Voldemort could team up with Alduin in some way, and the Dragonborn and Harry Potter have to work together to stop them.
One interesting idea could be a fanfic that focuses on the Marauders' time at Hogwarts. It could explore their pranks, friendships, and how they came to be the legends that we hear about in the original books. For example, showing how they created the Marauder's Map in more detail.
One interesting idea could be a fanfic where the Marauders attend Hogwarts during modern times. They'd have to deal with things like smartphones and social media while still maintaining their mischievous ways. Another could be a story that focuses on the lives of the house - elves after the events of the books, perhaps exploring their newfound freedom. And a third idea could be a fanfic about a new dark wizard emerging in the wizarding world years after Voldemort's defeat, and how the new generation of Hogwarts students respond.
A great 'Harry Potter fanfic' idea might be a story that delves deeper into the relationship between Snape and Lily. Maybe a fanfic where Snape has a chance to change the past and save Lily in a different way. Another idea is to write a fanfic about the ghosts in Hogwarts and their backstories, like how they died and why they chose to stay at the school. Additionally, a story where the Weasley twins open a magical joke shop in a different country and the challenges they face there would be really interesting.
One interesting idea could be exploring the lives of the minor characters more in - depth. For example, what was Neville Longbottom's life like during the summers at home? Another idea is to create an alternate ending to the series. Maybe Voldemort could have been redeemed instead of defeated. Also, a fanfic could focus on the magical creatures and their own society within the wizarding world.
One idea could be that Harry Potter and his friends accidentally get transported to the RWBY world. They could then use their magic in unique ways to help the RWBY characters fight Grimm. For example, Hermione could use her knowledge of spells to create new defenses against the Grimm that the RWBY characters haven't thought of before.
One interesting idea could be a crossover with 'Lord of the Rings'. Imagine Harry and his friends in Middle - earth, facing the dark forces there. They could learn new magic from the wizards in Middle - earth or teach their own brand of magic. Another idea is a crossover with 'Percy Jackson'. The demigods and the wizards could team up to fight a common enemy that threatens both the magical and the mythological worlds. Maybe they'd have to combine their powers and strategies.
One idea could be creating a new magical game within the Hogwarts world. For example, a game that combines elements of Quidditch and wizard dueling. The characters could form teams and compete in a tournament where they have to both fly on brooms and use spells against each other. This would add a new and exciting dynamic to the fanfic.
A really interesting concept would be Stiles being a time - traveler in the Harry Potter world. He could go back in time to witness important events in the wizarding world's history and even change some small things that have a big impact on the present in the fanfic's storyline.