AI sucks for fanfic.

I don’t know if it’s just me, but AI sucks for writing fanfic. I’m trying to write a fanfic about a favorite show of mine that was unfortunately cancelled after 3 seasons. I’ve asked ChatGPT, perplexity, copilot, mistral, Gemini, what happens at the end of season 3 (final season, I wanna make a hypothetical 4th season), and they get it all wrong, give me wrong answers or details. Does anyone have any good ais that are free, no subscription required that actually know their shit and are good for fanfic?