1. Is there any linkage or leakage between the Los Angeles reality, in which 815 never crashed, and the reality of our survivors back on island - survivors now not only of a plane crash, but an H-Bomb explosion? As I mentioned in my review of the premiere, Juliet's last moments, and what Miles told Sawyer about Juliet what wanted to tell Sawyer, are key. She seems to have been in touch with that world in which 815 never crashed, just before her death. Other possible evidence of linkage: Desmond the time traveler on the LAX plane. If there's a character that could move between two alternate realities, it would be Desmond, who can move through time. And Jack did have an expression, when we first see him on the plane, of possible deja vu - though that's the least clear, as far as evidence. But I'd say Juliet and Desmond are pretty impressive.
2. Has there been a history of either Jacob or the Nemesis taking over bodies of the dead before, just as the Nemesis took over Locke's? I'd say almost certainly yes, and that Christian Shephard on the island was likely Jacob in his body. Christian's body in a coffin was brought to the island on a plane in the same way as Locke's. I also think this makes it more likely that Claire is alive - it wasn't Christian's ghost that led her away, it was Jacob in Christian's body.
3. What happened to everyone else on the island after the H-Bomb went off? This is in some ways that most significant question - though #1, about linkage, is pretty important, too. One answer would be presumably everyone on the island died - because how could they live underwater? But ... why then did Jack, Kate, Sawyer, Hurley, Miles, Jin, (Juliet and Sayid at first) survive the blast? Why did the island itself? What happened with Sun and Richard and Lapidus? It's also not 100% clear - at least, not to me - about whether Jack, Kate, Hurley, etc are in the same time as Sun, Richard, etc - Jacob talks to Hurley after Jacob's dead, but Jacob may have the ability to time travel and who knows what else. For that matter (call this Question 3a), I'm not even sure whether Jack, Kate, etc on the island are in 2007 (where Sun and Richard are) or 2004 (the time of the alternate reality LAX). In any case, all of this suggests that something about the island and/or something about the people and/or who knows what else enabled some, all, many, just the people we saw, survive the blast. Which means ... all bets are off regarding who survived and who did not.
You gotta hand it to Lost. No matter how much is explained, all bets are forever off...
8-min podcast analysis of Lost Season 6 Premiere
See also: Lost Season 6 Double Premiere
More Lost - see : The Richard-Locke Compass Time Travel Loop ...
and Lost Returns in 5 Dimensions and 5.3: The Loops, The Bomb ... 5.4: A Saving Skip Back in Time ... 5.5 Two Time Loops and Mind Benders ... 5.6 A Lot of Questions ... 5.7 Bentham and Ben ... 5.8 True Love Ways ... 5.9 Two Times and a Baby ... 5.10 The Impossible Cannot Happen ... 5.11 Clockwork Perfect Time Travel ... 5.12: Ben v. Charles, and Locke' Slave ... 5.13: Lost Meets Star Wars and the Sixth Sense ... The Problem with Baby Aaron and the Return of the Oceanic Six ... 5.14: Eloise, Daniel, and Obsession Trumping Paradox ... 5.15: Moral Compasses in Motion ... Lost Season 5 Finale: Jacob and Locke
The Plot to Save Socrates
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