Terry O'Quinn, <EM>Lost</EM> Terry O'Quinn, Lost

This TV Guide reporter lucked into getting an advance copy of "The Brig," tonight's Locke-centric episode of Lost (10 pm/ET on ABC), and, having watched it, what can I say? It's one of the series' best. And I'm not just talking this season. Written by series masterminds Damon Lindelof and Carlton Cuse, it is, by turns, twisted, spine-chilling and emotionally stirring. Make that gut-wrenching. It grabs hold and doesn't let go, even after the last frame has smashed to black.

If you've watched the sneak-peek clip on this website, you already know that Locke — MIA from the canvas since early April, when he discovered his loser pop was in the island's magic box — shows up while Sawyer's taking a leak to reveal that he's kidnapped Ben. Oh, and he'd like Sawyer to kill him, thank you very much. But this being Lost, that's only the beginning of the story. What follows is a literal and metaphorical journey that's bound to irrevocably change two of the drama's most complicated and best-loved characters. Which, if we're lucky, will only lead to more stand-out episodes like this one.

Here's what else to look out for:

Big blanks get filled. Much the way that last season's Michael-centric episode "Three Minutes" shed light on what the grieving father had been up to since taking off to find Walt, "The Brig" fills in the blanks where Locke's recent time with the Others is concerned. Among the questions answered: What was Cooper's reaction to seeing his son? What was Ben's motive for leading Locke to his father? Why on earth would the Others let Locke stick around after he blew up their sub? And just how far will Locke go to learn the island's secrets? (You remember the lengths Michael was willing to go to get his son back, right?)

The Black Rock is back! The 19th-century wooden ship, first (and last) shown beached in the jungle during Season 1, is the backdrop for a chunk of tonight's action. Locke's prisoner is being held in the ship's titular brig. And somebody else shows up to pilfer some of its dynamite. Let's hope this somebody is more careful with it than our dearly departed Dr. Artz.

Josh Holloway and Terry O'Quinn knock this episode out of the park. But Holloway claims shooting its emotionally draining scenes took a toll. "Dude, it was intense, filming that s--t," he says. "It wore me out." Still, the two actors — who are good buds off screen — relished the rare opportunity to work together. Will they do more of it in the future? Holloway's not saying, though he does let this slip: "What happens with them, it f--ks Sawyer up pretty bad. It makes him colder and more distant." That can't be good news for his relationship with Kate.

No. Way. This week's installment includes the reveal of Lost's biggest character-cross yet. As in, bigger than Claire and Jack sharing the same father. And this jaw-dropper was set up way back in Season 1.  

The hits keep coming. Naomi the parachutist (played by Marsha Thomason) — who revealed last week that as far as the "outside" world was concerned, Flight 815's passengers died (!) when the plane crashed — isn't done dropping bombshells. Cindy the flight attendant isn't finished with the Others. And Richard (the intriguing Nestor Carbonell) is just getting started pulling strings. But you'll see what I mean by that next week.

Let our snazzy new Online Video Guide find you some Lost clips.

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