It can be argued that Lost is always at its best when it’s focusing on its key mysteries. It can also be argued that it’s at its best when it really hits into the core of a character. This week’s episode, focusing on the enigmatic and weaselly Benjamin Linus, fires both barrels, and the result is something that fans are already hailing as one of the series’ finest hours.

It’s hard to think that there was a time on Lost before Ben was added to the show.  He’s such an integral part of the series as a catalyst, an antagonist, and a walking mystery that it seems weird that the show ever made sense without him (some might argue that the show really didn’t make much sense back then anyway).  He’s the perfect conniving bastard, the sort of fellow that you just want to see get punched in the face–a real threat and an evil manipulator, but one whose personal flaws are so obvious that he doesn’t risk becoming some uninteresting, unbeatable uber-villain.

Season Six has had fun playing with the flash-sideways timeline to juxtapose characters and situations, but never has the juxtaposition been as strong and as poetic as it is here with our two Ben Linuses: one the former shell of an evil mastermind, and the other a mild-mannered history teacher who’s almost too afraid to want something more.  (Also, administering life-saving gas to your father in one timeline when you gassed him to death in another? I love you, Lost.)  Credit goes both to the show writers and to Michael Emerson as an actor for letting the audience believe that, yes, these two different people could be each other if circumstances were just different.

That’s where the tension and the drama comes in with the flash-sideways storyline this time around. We’ve seen, in the original timeline, what Ben is capable of, and he’s given the chance to be that manipulating bastard again. After a brilliant setup of the eponymous Dr. Linus giving a history lesson about a power-hungry man being exiled to an island, we’re reintroduced to Alex, this time in the form of Ben’s protege instead of (forcibly) adopted daughter. Aside from leaving me wondering if we’ll ever get to see flash-sideways Rousseau, this setup of Ben taking Alex under his wing is legitimately touching, and by the end of the episode, with the viewer knowing that any world’s Ben could still be “Ben,” there’s true uncertainty about what he’ll ultimately do.

The original Ben sacrifices Alex in order to hold on to his power, and the flash-sideways Dr. Linus sacrifices his shot at power to save Alex.  This show loves to highlight “good” and “bad” people, and to examine what makes people who and what they are.  Knowing that Benjamin Linus could make a choice like he does in the flash-sideways timeline helps the audience to believe that, in the original timeline, he could be seriously repentant.

If I had to put together a list of Lost‘s Top Ten Moments, the scene where we have Ben tearfully and plaintively tell Ilana about killing Jacob and losing Alex would absolutely be on there.  It’s a masterful performance, and the impact is made even more impressive in that it’s a legitimate note of sympathy for Ben, a man who has done so much wrong and harm, taken so many lives and ruined countless others. It doesn’t absolve him completely, of course, but it’s enough for Ilana to spare him.

We get plenty of other win snuck into the episode as well. Miles, who has been disappointingly scarce so far this season, gets a Crowning Moment of Awesome™ early on by pwning Ben in front of everyone (and later on, as well, by turning down Ben’s offer of bribery with knowledge of Nikki and Paulo’s diamonds, and then even later on by presumably digging them up).  Hurley has some hilarious dialogue exchanged with Richard, and that almost would have been enough, but then Jack has to go and pull a brass balls move of his own. “I’m willing to bet you that if Jacob went to that trouble, that he brought me to this island for a reason, and it’s not blow up sitting here with you right now.” Epic.

There’s some intriguing mystery left lingering about the whole “Candidates” thing, and about what it might mean to be touched by Jacob, or to be “gifted” by Jacob. Ilana and Richard clearly have some of the answers, and Ben might, as well.

I also want to see how fucked Jin and Kate are, tagging along with the Man in Black. It probably sucks to be them right now.