Maybe the Fem Harry Potter is being hunted by Voldemort's followers in a new and unexpected way. The NCIS agents rescue her, but then find out that there are spells on her that are affecting the Muggle world around them. They need to find a way to break the spells while also keeping her safe from the Death Eaters. This could lead to some interesting interactions between the two very different worlds.
A plot twist could be that the NCIS team has a member who has some latent magical ability that is awakened by being in contact with Fem Harry Potter. This person then becomes crucial in understanding the magical threats against her. They might also discover that there is a much larger conspiracy at play that involves both the magical and Muggle worlds, and they have to work together with the wizarding community to save not just Fem Harry Potter, but also prevent a disaster in the Muggle world.
The plot could involve a magical artifact that Harry Potter is trying to protect. This artifact has somehow made its way into the world of NCIS. Dark wizards want to get their hands on it and will stop at nothing. Harry is in over his head as he tries to deal with both the Muggle law enforcement and the powerful magic of his enemies. NCIS agents, with their own code of honor and sense of justice, step in to rescue Harry. They start to learn about the magical world as they help him, and together they come up with a plan to keep the artifact safe and get Harry back to Hogwarts.
One possible plot twist could be that the Queen discovers Harry's magical abilities early on and decides to train her in a special way, perhaps combining magic with royal etiquette. This would give Harry a unique advantage in the wizarding world.
A plot twist could be related to Fem Harry Potter's magical abilities. Since she is raised by Crowley, she might develop some unique magical skills that are a blend of wizarding magic and Crowley's own brand of 'power'. This could make her a target for various groups in the wizarding world who either want to use her for their own gains or are afraid of her new - found powers. Also, Crowley might have some enemies in the wizarding world that he has never revealed to Fem Harry Potter. When these enemies discover her existence, they target her to get back at Crowley, putting her in great danger and forcing her to rely on skills and knowledge she has learned from Crowley to survive.
A possible plot twist is that Fem Harry Potter discovers a magical item that links her to Harley Quinn's world in some way. Maybe it transports her there briefly, and she has to learn to adapt to Harley's Gotham while also bringing some of her Hogwarts magic. This could create a really interesting clash of two very different universes.
There could be some comical interactions. For example, the NCIS agents might try to use their standard interrogation techniques on Fem Harry Potter, which would be completely ineffective since she's used to a different set of rules in the wizarding world. Meanwhile, Harry might accidentally use magic in front of them in a moment of panic, causing chaos. As they get to know each other better, the NCIS agents could start to learn some basic magic defense spells from Harry, while Harry learns about Muggle self - defense and investigation methods from the agents.
In this fanfiction, perhaps Harry Potter is brought into NCIS because there are rumors of a wizard - made weapon being used in crimes. He would have to navigate the non - magical world of law enforcement while also keeping his own magical identity a secret. His owl, Hedwig, could be used to send messages in a discreet way that NCIS could benefit from. He might also introduce some of his wizard friends, like Hermione, to help with research using magic - enhanced techniques.
One possible plot could be that Harry is wrongly accused of a crime in the wizarding world, perhaps something related to dark magic. The police, who might be a new magical law enforcement unit, rescue him from an angry mob. They then help him clear his name by finding the real culprit, who could be a Death Eater in disguise trying to frame Harry to cause chaos in the post - Voldemort era.
The plot could involve the goblins rescuing Harry when he is being wrongly accused of a crime in the wizarding world. They could believe in his innocence and use their unique skills and knowledge of magic to keep him safe. Maybe they help him prove his innocence later on. They might also have their own motives for helping Harry, like they see him as a key to some sort of change in the relationship between wizards and goblins.
One possible plot twist could be that Fem Harry discovers one of the orphans has a magical ability she's never seen before. This could lead to a whole new adventure as she tries to figure out what it means and how to help the child control it.
A possible plot twist is that her vampire heritage affects her relationship with magic. Maybe spells work differently for her because of her half - vampire nature. For example, some light - based spells might be harder for her to perform. Also, she could have a special connection to nocturnal magical creatures that normal wizards don't. This could lead to her getting involved in some dangerous adventures in the Forbidden Forest at night.