What are some interesting plot ideas for 'the great mouse detective oc fanfiction'?

An OC who is a street - smart mouse with a network of informants all over the city could be interesting. This OC could come across a strange occurrence that they think Basil should know about, leading to a new adventure. They could provide Basil with valuable leads from their connections on the streets.

One idea could be a crossover with Sherlock Holmes in the human world. The great mouse detective could team up with Holmes to solve a mystery that spans both the mouse and human realms. Maybe there's a villain causing chaos in both worlds and their combined skills are needed.

One idea could be Basil solving a mystery in a new, strange part of the mouse city, like an abandoned underground area filled with old secrets. Another could be Basil teaming up with a new, young mouse detective in training to solve a case that's baffling the entire mouse detective community. Or perhaps a story where Basil has to solve a mystery on a ship sailing to a far - off mouse - inhabited island.

One idea could be an OC who is a detective trainee and teams up with Detective Pikachu to solve a mystery in a new part of the Pokemon world. Maybe they are investigating a series of disappearances of rare Pokemon. Another plot could involve an OC with a special ability to communicate with certain types of Pokemon that Pikachu can't, and together they use their combined skills to stop a villain who wants to use these Pokemon for evil.

One interesting story could be about the great mouse detective solving a mystery in an old, abandoned cheese factory. The clues are hidden among the cheese wheels and old machinery.

One idea could be creating an OC who is a master of disguise, like Conan, but with a unique backstory. Maybe they are from a different country and have their own reasons for getting involved in the detective work in Japan. Another idea is an OC that has a special gadget - something that hasn't been seen in the original series yet, like a device that can analyze poisons instantly. And a third idea could be an OC who is a childhood friend of Shinichi's that has some hidden talents related to solving mysteries that come to light after his transformation into Conan.

One idea could be a mouse that has magical powers and becomes friends with Harry. It could help him in secret ways, like finding hidden passages in Hogwarts by squeezing into tiny holes that humans can't reach.

Perhaps the OC is a foreign traveler who comes to visit the Great Wall. While there, they get lost in a restricted area and find a hidden passage. Inside, they find a community of people who have been living secretly near the wall for centuries. The OC becomes involved in their internal politics and helps them deal with a threat from the outside world that could expose their existence and endanger the Great Wall.

Well, you could have an OC that is a childhood friend of Shinichi who has a photographic memory. This OC could recall small details from their past that end up being crucial in solving current cases. Or perhaps an OC who is an expert in a very specific field, like ancient languages, and Conan has to rely on this OC's knowledge when a case involves old inscriptions or manuscripts. Also, an OC who has a connection to the Black Organization, either as a former member trying to reform or someone unknowingly involved in their plans, could add a lot of drama to the fanfiction.

She could be turned into a mouse - like creature by an experimental akuma attack. As a mouse, she discovers new parts of Paris that are usually hidden from humans. This could include secret underground tunnels or the rooftops in a whole new perspective. She might also meet other kwamis who are more active in these hidden areas.