2010.

A few questions.

1. They never explain how they get into each others dreams. Or did I miss that? That seems like a key part of the whole thing
If the answer is just magic movie mechanism that is glossed over, I can accept that, but just want to make sure I’m not missing something.
2. How does Yusuf get woken up? He’s out in the van and in his seatbelt. Why didn’t they unbuckle him, and how’d he wake up when it seemed the jump didn’t wake him?
3. How did Saito and Cobb wake up without a jump in the limbo level?

I’m sure there are about 20 other unanswered questions, but those were the three that stood out to me the most.