I want a movie based on Perdido Street Station by China Mieville. I'd call it gritty steampunk fantasy. Basic plot of the book is a bird-man has been punished by having his ability to fly taken away from him. He goes to the city to find someome who might be able to make him fly again. The person he finds is a bit of a rogue scientist, and he researches flight at first by collecting flying critters, and things that will change into flying critters like caterpillars. He ends up accidentally getting ahold of a caterpillar that turns into a dangerous and terrifying flying critter.

There's a lot to the book outside of the above, such things as evil politicians, organized crime, strange drugs, a virus in steam-powered automatons that makes them self-aware, underground newspapers, a race of people that can make water into solid self supporting shapes, various different races of intelligent beings, and people who have been punished by having machinery or parts of animals magically attached to them, and in general a lot of good world building.