
Graham Roland makes his LOST co-writing debut in an episode which rivals The Economist for my favorite Sayid-centric.
Roland and co-writer Paul Zbyszewski throw us a curveball (pun intended, major points if you get it) right off the bat in the flash-sideways (FS). Sayid arrives at a doorstep and is greeted by Nadia's warm smile — but she's married to... wot? His brother Omer!?
After Omer finds himself swamped in debt, the thugs to which he is indebted decide to rough him up. They don't stop there, though — they nab Sayid and take him to a restaurant for further "persuasion." The ring leader of these thugs turns out to be none other than Keamy, and he's apparently quite skilled in the culinary arts. But alas, Sayid's cooking up some revenge of his own (another pun intended, this one much worse) and clears the room in short order. A distant pounding noise leads Sayid to discover his first FS-Lostie connection: Jin.
Things get extremely intense on the island, with fake Locke (FLocke) sending Claire into the Temple to summon Dogen. Dogen seems less interested in Claire than killing Sayid, so he sends him out to kill FLocke with a fancy dagger. Not only did the stabbing fail, it opened the door to further corruption and coercion by FLocke.
Sayid would return to confront Dogen yet again, with fatal results this time around. Sayid drowns Dogen and slits Lennon's throat, paving the way for FLocke to enter the Temple and obliterate everyone in his path. Ilana's team arrives in time to lead the main characters to safety but the redshirts are splattered into every corner.
This would pretty much conclude the Temple arc, which some LOST fans insist was a waste of time. I respectfully disagree, especially after the Redux rewatch. It was the next logical step in the mythology since the Temple had been briefly hinted at in several prior seasons, and as a bonus it was an atmospheric set which significantly amplified the theme of one's inner struggle of good versus evil.

Sundown just wouldn't have worked with anyone else but Naveen Andrews as its focus. Sayid had established five seasons' worth of ruthlessness and Sundown was the big payoff. Other than his sacrifice in The Candidate, this was Sayid's last significant contribution to the series and it was a memorable one.
Kevin Durand was positively brilliant as Martin Keamy. This was by far his most entertaining performance in the series, surpassing even his own arc in Season 4. Don't get me wrong, he was still very much a repugnant jackass but he was cracking me up every step of the way.
Since this was Dogen and Lennon's swan song I should mention why I haven't included them in recent reviews: I found them both to be average. That's not entirely their fault, for they were never intended to be fully invested characters.

Bobby Roth has a pretty good track record. Sundown was his third directorial effort on LOST, with the previous two being The Man Behind the Curtain and Whatever Happened, Happened. Not bad at all.
A major round of kudos for the directing and coordination of Sayid's epic fist-fight with Dogen, even if I was a little surprised by the winner.
But of course, even that scene pales in comparison to the final 12 minutes of the episode. The drowning of Dogen was horrifying enough but Smokey's rampage through the Temple was awe-inspiring, especially during moments like the one which sent Kate falling into Claire's pit. It literally looked and felt like Hell itself had been unleashed.
One of my favorite moments of the series would follow, a slow-mo sequence of Sayid and Claire walking through the flaming destruction. Cinematic excellence.

Every time I watch Sundown I'm anxious to get to the last fifteen minutes or so, but I've got to break that habit. The episode as a whole has plenty to offer beyond the Temple's destruction, including one of the better melee scenes of the series and the memorable flash-sideways encounter with Keamy.
The destruction of the Temple is moderately significant, and I say "moderate" because I realize the importance of Dogen and Lennon were debatable in the first place. At the very least, it's important that Sayid officially joins FLocke's ranks and helps establish which Losties belong to which teams.

When I hear the word "atmosphere" and apply it to LOST, Sundown is THE episode that comes to mind. Simply put, there is no scene more bone-chilling, more atmospheric, than Claire and Sayid walking through the destroyed temple. A huge part of that is the music that plays while it's unfolding — a haunting version of "Catch A Falling Star", as in the lullaby Christian once sang to Claire when she was a child.
That music was stuck in my head for days after Sundown first aired. I just couldn't shake it out of my system, it was such a dark moment but visually and thematically. I almost expect Sayid to go past the point of no return, but for sweet and innocent Claire to follow suit proved to me that Season 6 just upped the ante.