1. They're not looking for gold. The want to make an Inception, planting an idea in Robert Fischer's mind to split up his father's company.
Saito said that his company is the last company who's still standing between Fischer's company and the total energy dominates. And his company can no longer compete. This would make Fischer's company takes over half of the entire world's energy marketplace. If this happens, Fischer company will become a new global superpower dominator.
Saito: The world needs Robert Fischer to change his mind.
Cobb: You're asking me for Inception. I hope you do understand the gravity of that request.
Cobb: The seed that we planted in this man's mind may change everything.
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2. To make an Inception they have to plant the idea deep enough, so they make 3 layers dream. In each layer, the Dreamer (the Architect who build the dream world) must stay in that layer while the others can go into the deeper dream layer.
DREAM LEVELS
^ 1 Rainy City - The Van [Yusuf's dream]
Yusuf drank a lot of champagne in the “real world” on the plane, so when he goes to sleep he has to pee (hence the rainfall).
^ 2 Hotel - Room 528 [Arthur's dream]
When the van Yusuf is driving goes off the bridge and is flying through the air, Aurthur’s “body” is suspended in air, which is why gravity in the hotel level of the dream goes haywire – as the dreamer’s body is shifted and moved, it effects the physics of the dream he’s dreaming, since the mind (and inner-ear) is registering the change in gravity.
^ 3 Snow Fortress in the mountain - Hospital room [Eames' dream]
Fischer enters his own Projection in the safe.
^ 4 Mal's World where Mal hides Fischer [Cobb's dream - Fischer's Limbo]
Ariadne drops a line early on about the fact that the extractor team can bring elements of their own subconscious into the dream levels if they’re not careful, and since Cobb has spent time in Limbo and has a raging subconscious, his dream includes his memory of the city he and Mal built for themselves.
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