301 A Tale of Two Cities 9.4
Legendary cold open.
302 The Glass Ballerina 8.7
Decent episode. Engaging enough. But, as usual, Sun's flashback is a bit weak and overextended.
303 Further Instructions 7.7
The sweat lodge sequence is wonderful, but otherwise Locke's content is underwhelming. Meanwhile, Desmond's new clairvoyance is exciting.
304 Every Man for Himself 9.6
This is where Jack/Kate/Sawyer's imprisonment first peaks. So much going on from beginning to end. Sawyer's flashback, charactersitically, is brief and excellent.
305 The Cost of Living 7.3
Eko's flashback: okay. John's adventure: garbage (some of his weirdest dialogue ever, plus overexposition). Jack's content: fantastic (and almost certainly written by someone else).
306 I Do 10.0
Wow. The captive story definitely achieves its full potential here. Emotional intensity and complexity dominate. Dynamite performances from beginning to end. Visually masterful. This is probably the best mystery-free episode of the show.
307 Not in Portland 9.3
More emotional intensity, with a few helpings of mythology.
308 Flashes Before Your Eyes 9.4
The writing is surprisingly mixed. But conceptually, a huge leap forward. Lots of easter eggs, too... Charlie sings to Desmond: "maybe you're gonna be the one who saves me." Earlier, "Building A Mystery" plays on the clock radio.
309 Stranger in a Strange Land 7.0
The flashback is pointless. The island stuff is more than passable, though. Not the sharpest episode, but hardly the worst ever, as many believe. It benefits from Matthew Fox's full commitment.
310 Tricia Tanaka Is Dead 8.0
Flawed but fun.
311 Enter 77 8.4
A decent adventure. Some of the mythology is tantalizing (chess game). But some feels silly ("shoot me"). Contrast with 313 — sort of in a different category.
312 Par Avion 9.6
Claire's psyche and her dynamic with Charlie both come to life here. Music is amazing throughout. Has one of the best episode endings ever!
313 The Man from Tallahassee 10.0
Powerful and pitch-perfect from beginning to end. A smart episode executed to its full potential. Another one that epitomizes the show.
314 Exposé 9.5
A unique (though not flawless) gem. Wonderfully indulgent. You can feel the creative energy that went into this one.
315 Left Behind 9.3
Smart episode with a lot of heart. Each character moment feels remarkably true to the show.
316 One of Us 9.0
Decent, but stretches a bit. We reach a Juliet saturation point. Amazing ending, though.
317 Catch-22 8.4
A solid "Losties hangin' out" episode. But the writing is mixed, and Desmond's flashes are quite dumbed down. They still don't entirely trust us with Desmond's content.
318 D.O.C. 7.4
Subpar episode. Overloaded with plot recapping. Sun's flashback is better than usual, though. We find out Jin's "promotion" was her fault. Great cliffhanger.
319 The Brig 9.1
Mythology feels a bit off (especially compared to the next ep), but everything with Locke's dad is really intense.
320 The Man Behind the Curtain 9.8
Jacob's cabin! Ben's backstory! Dharma! There's so much fresh discovery here, so much to chew on, and the execution feels right.
321 Greatest Hits 10.0
A perfect episode. Emotional and exciting throughout. Basically part 1 of the finale.
322 Through the Looking Glass (Part 1) 10.0
This is one of those finale Part 1s that has a lot of meat on it. Contrast with 123 and even 223.
323 Through the Looking Glass (Part 2) 10.0
Layers upon layers of thematic depth here. And that final scene is just transcendently great. It's a clear signal that what comes next — the second half of Lost — will be taking things to a new level.
In order of favoriteness:
10.0 306 I Do
10.0 323 Through the Looking Glass (Part 2)
10.0 321 Greatest Hits
10.0 313 The Man from Tallahassee
10.0 322 Through the Looking Glass (Part 1)
9.8 320 The Man Behind the Curtain
9.6 304 Every Man for Himself
9.6 312 Par Avion
9.5 314 Exposé
9.4 301 A Tale of Two Cities
9.4 308 Flashes Before Your Eyes
9.3 315 Left Behind
9.3 307 Not in Portland
9.1 319 The Brig
9.0 316 One of Us
8.7 302 The Glass Ballerina
8.4 311 Enter 77
8.4 317 Catch-22
8.0 310 Tricia Tanaka Is Dead
7.7 303 Further Instructions
7.4 318 D.O.C.
7.3 305 The Cost of Living
7.0 309 Stranger in a Strange Land