What are some interesting ideas for a 'Back to the Future' crossover fanfiction?

One idea could be a crossover with 'Doctor Who'. The DeLorean could time - travel to a universe where the Doctor exists, and they team up to fix a time rift that's threatening both their timelines. Maybe Marty and the Doctor have to figure out how to combine the technology of the TARDIS and the DeLorean to set things right.

A crossover with the Star Wars universe would be cool. Future Trunks could find himself on a planet in the Star Wars galaxy. Maybe he has to help the Jedi fight against the Sith. His superhuman strength and ki blasts would be a new and powerful element in the Star Wars battles. He could learn about the Force while also teaching the Jedi about ki energy.

One idea could be a crossover with the Dragon Ball Super universe. Future Gohan could meet the present - day Goku and Vegeta. They could train together and learn new techniques from each other. Another plot could involve a crossover with the Naruto universe. Gohan might use his ki powers in the ninja world, and perhaps have to face off against powerful ninja like Naruto or Sasuke. He could also learn some ninja skills in return.

One idea could be a crossover with "Adventure Time". Finn and Jake could visit Beach City and interact with the Crystal Gems. They could go on a mission together to stop a new threat that combines the magic of both universes.

One idea could be exploring how the future technology in 2015 from the fanfic affects the daily lives of the characters more deeply. For example, how do the flying cars impact traffic rules and social interactions? Another could be a new character introduced in the fanfic who has a special ability related to the time - travel technology and how that changes the story's dynamic. Maybe this character can manipulate time in a different way than the original characters, leading to new adventures and challenges.

Well, you could write a 'Back to the Future' fan fiction about a time when the DeLorean time machine malfunctions and sends Marty and Doc to a completely different era, like ancient Rome. They'd have to figure out how to get back while dealing with the culture shock and potential historical impacts they might make. Or perhaps a story where a future version of Marty comes back to his present time to warn himself about a coming disaster related to time travel. Another option is to create a fan fic where the time machine's flux capacitor starts to act up and creates mini - time portals all over Hill Valley, causing chaos that Marty and Doc have to sort out.

A plot idea could be that the Time - Turner in Harry Potter is actually an ancient magical version of the Flux Capacitor. Hermione discovers this connection while researching in the library. She then tries to build a device that can combine the two technologies. This leads to her accidentally traveling to the Back to the Future universe. There, she meets Marty McFly and they have to work together to fix the time rift that her experiment created.

One idea could be a crossover with the Dragon Ball Super universe where Future Trunks teams up with Goku Black from an alternate timeline. They could be forced to work together against a new, powerful enemy that threatens both their timelines. Another plot could involve a crossover with the Naruto universe. Future Trunks could end up in the Hidden Leaf Village and learn about chakra. He might then combine his ki powers with some ninja techniques to fight a common foe. A third idea is a crossover with the One Piece world. Future Trunks could land on the Grand Line and join forces with the Straw Hat Pirates. They would have to face off against the Marines and other pirates while also trying to find a way for Trunks to get back to his own world.

One idea could be exploring how Naruto's children deal with new threats to the Hidden Leaf Village. Maybe they face a villain who has found a way to use ancient, forbidden jutsu that Naruto and his friends had long forgotten about.

One idea could be Naruto's son or daughter discovers a new and powerful jutsu that was lost in time. This jutsu could potentially change the balance of power in the ninja world.