Desmond once again takes center stage with his tale of hatch implosions, star-crossed love, and now, trippy time-travel theories. This episode was probably the biggest structural departure of the show since the "Other 48 Days" Tailie episode last year; the entire middle was devoted to an uninterrupted Desmond flashback. Only it wasn't a flashback exactly -- and suddenly I realize trying to explain this on paper makes it sound a lot more confusing than it was. It was a flashback of what happened to him after he turned the hatch's fail-safe key, which was itself a journey back in time to when he was in London with Penelope. Only he still had memories of being on the island. Got it?

Cool, we're all good then. Do to the episode being very Desmond-centric, and the plot diving deeper into the rabbit's hole of time travel, it felt at times like not an episode in a series, but a stand-alone thriller about a man journeying through time to try to get things right with the one he loves. Think about it -- you extract Desmond's story from everyone else's, make a few changes, and you got an above-average feature-length sci-fi thriller of a screenplay on your hands (with the ending as yet unwritten). That's my screenwriting mind talking. But still. It'd be cool.

I'm always in favor of giving as many cast members as much screen time as possible -- the ridiculously heavy focus on Jack/Kate/Sawyer in the fall in part led to the loss of viewers they're experiencing now -- but I respected this episode's focus. Still, it would be nice to get more than one line from Sayid.

Anyway, I'm not going to bother summarizing what happened with Desmond's flashback because you've already seen the episode, right? Let's get right to the theorizing:

• The white-haired woman explained that the universe has a way of snapping back if you attempt to change things -- you can save the man in the red shoes from death now, but he'll die later from something else. I seem to recall learning this as the Elastic Theory of time travel, but apparently it's also called Determinism. In other words, fate is pre-decided -- but Desmond can change things and make choices -- so does free will exist or not?
  

• The good folks at EW also noticed this, but unlike me, actually drew some conclusions from it. In their own Lost recap they provide insight into Desmond with respect to the philosopher he's named after, David Hume. According to them:
  "Basically, Hume's theory of compatibilism posits that free will and determinism both exist, and that what we do with our lives is essentially the result of these two concepts butting against each other. In other words...Desmond Hume is living one of David Hume's theories."

• Me again. Borrowing a page from our dear departed Mr. Eko, compatibilism actually sounds a heck of a lot like the general version of Christianity, especially as explained by St. Augustine (who unfortunately has yet to have a character get named after him). Free will exists (if it didn't, there would be no faith, and therefore no God, the reasoning goes), but God also has a "plan" for everyone that guides them through life. Will the parallel be made, or is it lost forever along with Eko and his haunting monologues? Either way, it's pretty cool.

• 100 points to you if you've noticed that the last three bullets have all been the continuation of one though, therefore making the bullets completely unnecessary.

• To me, the white-haired woman was a deus ex machina of the best possible order. I really hope they don't try to explain her, and I really hope fans don't expect them to. She shows up in a mysterious way, explains to Desmond what's going on, and disappears. It was a well-done example of a normally arbitrary device. But to the curious: who exactly was she? She knew about the island, etc, but that doesn't mean she was in any way associated with Dharma or the show's mysteries -- she knew the red-shoed man's future, too. I'm perfectly content to say that she was a deus ex machina literally -- a god in the machine.

All right, enough of the ruminations. What do you guys think about the ending shocker? Is Charlie really doomed? Or will determinism be proven wrong? And exactly how much do you think we'll find out about the Others next episode? At least the sporadically-appearing and previously-kidnapped flight attendant is back, right?

Instant prediction: a few episodes down the line, an integrated and seemingly-fine Karl shockingly kills Charlie because of the programming he was subject to during his brainwashing. Hey, it'd be a cool moment.