One idea could be that a powerful villain uses a new technology to mind control Batman and forces him to carry out crimes in Gotham. This would create a great internal conflict for Batman when he eventually breaks free and has to deal with the consequences of his actions while under control.
Another plot could be that a mad scientist creates a device that can mind control people from a distance. He decides to test it on Batman. Batman, while being controlled, starts to give away the secrets of the Batcave and the identities of his allies. His friends like Alfred and Robin then have to race against time to reverse the mind control and save Batman and the entire Bat - family from the scientist's clutches.
Perhaps a mind - controlling alien entity arrives in Gotham and targets Batman. It uses his skills and knowledge to try and take over the city. The other heroes in the DC universe then have to figure out how to free Batman and stop the alien's plan. They might have to face a Batman who is using all his strategic abilities against them while being controlled.
One idea could be that a powerful wizard mind - controls a young virgin maiden in a medieval - like world. He uses her to carry out his secret plans in the royal court without anyone suspecting the innocent - looking girl. The maiden gradually becomes aware of the control but struggles to break free.
A story could be about a sister who discovers an old family secret that has been hidden for generations. She then embarks on a journey to uncover the truth behind the secret, dealing with family history, mystery, and self - discovery along the way.
A more psychological approach could be a character who willingly enters a mind - controlled state as part of an experiment. But then things go wrong, and they start to lose their sense of self. The fan fiction could explore their internal struggle as they try to regain control of their mind.
The Joker would be a great choice. He could use some new - fangled chemical or device to mind control Batman. Imagine the chaos he could create with a mind - controlled Dark Knight at his beck and call. He might make Batman do really out - of - character things like laughing hysterically while committing crimes.
One idea could be that Raven is in danger from a new dark magic threat and Batman, with his detective skills, helps her track down the source. They start to learn from each other, Raven about Batman's human tenacity and Batman about Raven's otherworldly powers.
One idea could be exploring Bruce Wayne's early training in more detail. Show his struggles and how he overcame them. For example, his first encounters with Ra's al Ghul's League of Shadows could be more in - depth, with new challenges and characters added.
One idea could be that Robin gets trapped in an alternate dimension where the villains are in control and Batman has to figure out a way to bring him back. Another could be a story where Batman is injured and Robin has to take on a major villain alone, learning to trust his own instincts more. Maybe a plot where they encounter a new, powerful ally who turns out to have a hidden agenda that threatens Gotham.
One idea could be that Batman and Supergirl team up to stop a powerful alien threat that is beyond the capabilities of either of them alone. They start off distrusting each other due to their different methods, but as they face challenges, they learn to work together and respect one another's skills.
A plot could involve Batman investigating a mystery that has ties to Themiscyra. For example, some ancient artifacts from Themiscyra are showing up in Gotham's black market. As he delves deeper, he discovers a connection to a long - lost Amazonian prophecy. Or perhaps there's a character from Themiscyra who has come to Gotham seeking Batman's help to save her homeland from an internal power struggle.
One idea could be that the Witchblade somehow ends up in Gotham City. Batman initially suspects it to be a new weapon in the hands of some villain. But as he investigates, he discovers the unique power and origin of the Witchblade. Maybe the Witchblade chooses Batman as its wielder for a short time to fight against a powerful supernatural threat that Gotham has never faced before.