I have an idea for a video game, what I have to do next?

Hi I just got an idea about a video game, so I started to expand it on my computer. But still, I'm confused. I just started writing as The Game video would be. I do not know if I write corect though. Must be like a movie script? After I finished writing it, what next? I thought of sending it to a company's video games (Ubisoft Romania - Peter Jackson's King's King Kong on PC guys). I need to send them just the script, or I have to send them something? Someone is helping me doing some art, so I can show Ubisoft (or any company would take the idea) as I want it. I'm waiting for some answers. Thanks:)

Dont send them a script coz they do not buy it if the already have your script Theyll steal it: P u need to know them: P or give them an idea abt it: P

Best PC Game for Kids (Jetix Kids Awards Romania 2006)

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