So why did the Josh Trank Fantastic Four film fail so miserably? I know that's a harsh question, but it has to be asked and the folks at ScreenCrush endeavored to find out. It sounds like everyone wanted something different. Writer Jeremy Slater wanted to make a giant, epic film while director Trank wanted something grounded and gritty… and producer Simon Kinberg wanted something that would make sense and come in under budget. All three got writing credit.
Slater ended up doing 10 to 15 different drafts of the film in six months. His version would have been very expensive and would feature multiple villains including an early fight with Annihilus. This is what he told Matt Singer.
In addition to Annihilus and the Negative Zone, we had Doctor Doom declaring war against the civilized world, the Mole Man unleashing a 60 foot genetically-engineered monster in downtown Manhattan, a commando raid on the Baxter Foundation, a Saving Private Ryan-style finale pitting our heroes against an army of Doombots in war-torn Latveria, and a post-credit teaser featuring Galactus and the Silver Surfer destroying an entire planet. We had monsters and aliens and Fantasticars and a cute spherical H.E.R.B.I.E. robot that was basically BB-8 two years before BB-8 ever existed. And if you think all of that sounds great…well, yeah, we did, too. The problem was, it would have also been massively, MASSIVELY expensive.
Well, you can say what you want about Slater's overly ambitious version of the script… but if nothing else, he seemed to be the only one that remembered that part of the film title was 'Fantastic'.