“…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.
And, when they’re in the warehouse on the 1st layer [while Cobb told them that they'll go into Limbo if they die in a sedated dreams], Arthur said since they shared a dream together, if they go to Limbo, it would be a projection of what’s left from a subconcious mind of the people in that dream, and in this case, it’s Cobb’s Limbo [because he was in a Limbo before]. This explains why Fischer’s Limbo is the same as Cobb and Mal’s.
After Ariadne found Fischer, she waited first until she sees the lighting in the sky [which indicates Eames is giving an electric jolt to Fischer as the kick from higher level]. Then she pushes Fischer, making him fall, this is the kick from 4th level.
After that, Ariadne didn’t just jump right away. She jumps when the buildings started to crushing down [this means the base under the hospital room in 3rd level is being blown apart]. So she get her kick from free fall, and the kick from the 3rd level too.
This implies to the other levels too. At 3rd level the room falls down because the lower base is blown by explosives. At 2nd, Arthur uses the explotion energy to urge the elevator falling down. At 1st the van hits the river.
The Van that falls into the river has other use than just a kick. It makes Fischer thinks that the kidnapers are drowning, then he and his uncle Brownings swim to the surface. Browning said sorry for wanting to prevent Fischer from finding the inherit [and to stop Fischer from being himself and break apart the company].
At 1st layer, they just have to wait until the sedatives runs out, which is before the plane landed.
How they can stay in 1st layer without being attacked, I am assuming it’s because Fischer thought he’s actually back in reality & he’s not feeling threatened, also he got relieved after getting the secret of his father’s feeling towards him, maybe this has “switched off” the defense system in his mind.
How Cobb & Saito were able to come back? Simple, with the pistol.
They shot themselves in time when the sedative already runs out, when Cobb & Saito wakes up on the plane, Fischer and the other team are already awake.
How do you know the sedatives already runs out? Fischer already sits firmly, Eames is wiping face with hot towel, Arthur & Ariadne [secretly] looking at him as if they’re wondering if Cobb would ever wake up.
One way to know you’re in a dream is that you couldn’t remember how you get there. When Cobb wakes up in the plane, he’s back to where he was, he’s not waking up in some unknown place with no explanation of how he got there.
When Cobb wakes up, he looked like trying to regain his senses, his expression shows that he’s thinking and wondering if he’s realy awake. Saito wakes up in kinda awkward position and has a hard-to-explain expression on his face. Old soul that finally returns to youthly body. Then he honor his word, and make the call to drop the charges on Cobb. And as Cobb walks through the immigration check and drags his luggage out, his worried and relieved expression is really shown….”
- Volokh – Understanding Inception “…here’s an alternate understanding. Cobb, the guy whose dream we’re watching, is not in true Reality (level 0) a professional dreamer who can get into other people’s dreams. He’s just a regular guy having a very elaborate dream. And it happens to be a dream in which Cobb learns some...
- FastCoDesign – 2010 Inception Infographic by Daniel Wang –http://www.fastcodesign.com/node/1662131...
- HalPhillips – Inception “…When the film ends, Cobb wakes up. The entire film has been a dream that helped him realize how he needs to handle his wife’s death. Ariadne’s work is done. As for who arranged the inception, and why? It doesn’t really make a difference. Maybe someone benevolent wanted to help...
- JimboRant – It was all a Dream “Sequence of Events The movie starts in limbo, then goes to Cobb and Arthur’s attempt at stealing an idea from Saito. Ok first let me note that the idea was never specific. Like anything in the dream world it is not really real. Therefore there was never really an idea...
- MovieFone – ‘Inception’ Ending and Theories: What Just Happened?! “…• So if it was a dream…? If it was real, of course, then there’s not a whole lot to strain your brain over. But if that top is still spinning on some cutting room floor, then a whole new slew of questions open up. Are the other members of...