Imagine there’s this universe where everyone thought the first Star Wars film was some awful kiddie flick, so a low-budget sequel was released in 1980 starring only Luke and Leia. The decidedly-not-brother-and-sister tried to recruit people to the Rebellion, got stuck on a planet with a mysterious Force-enhancing crystal and… got into a mud fight?
This is the alternate universe we might have lived in. Thankfully, Star Wars broke the box office bank and Alan Dean Foster’s Splinter of the Mind’s Eye was never a film. In fact, looking at it now, it’s only barely reconcilable as canon in the Expanded Universe. (And that’s saying something.)
[There’s a book where Luke slaps Leia?]