The stakes are rising. No doubt about it.

The Others are out there, and they mean harm: They blew up the escape raft and kidnapped young Walt. The French-speaking "mad"-moiselle took Claire's baby for a few heart-stopping hours. And that unseen monster is still rustling in the trees.

On the outskirts of Honolulu in a warehouse converted into what looks like a cheesy Hawaiian-themed restaurant with fake caves, lit tiki torches, wood-chip floors and plastic tropical plants, some of the stars of the hit ABC series "Lost" have assembled to shoot a scene for the second-season premiere (airing tonight). It promises to pick up the many threads left hanging in last season's two-hour finale.

On the set, Matthew Fox (Jack) stands atop a mound of lava rocks to share disturbing news with the remaining survivors of Flight 815: One of the castaways, high school teacher Arzt, is dead, having exploded in the finale.

Mixed in with the crowd of extras are familiar faces from the series' freshman year: Naveen Andrews (Sayid), Maggie Grace (Shannon), Yunjin Kim (Sun), Evangeline Lilly (Kate), Dominic Monaghan (Charlie) and Emilie de Ravin (Claire), who is dangling Claire's infant son Aaron — actually, a disturbingly lifelike $8,000 replica — by one arm.

Director Jack Bender instructs the extras to do another take. This time, he kids, "with acting," as they respond to Jack's announcement that Arzt exploded while trying to transport dynamite.

"Be careful with your gasps; he's not the first ... (death)," Bender reminds them. "Was it that (expletive) noise out there? That monster? Let the panic bubble up. Think, 'Next time, it could be me.' "

That's a particularly painful sting for the stars. The sudden dismissal late last season of series regular Ian Somerhalder (Boone) has made them all realize that this dangerous island does not guarantee them the same job security as, say, the "Desperate Housewives" of the only slightly less dangerous Wisteria Lane.

"It's painful and nerve-racking," says Josh Holloway (Sawyer) of the producers' secret hit list. Holloway was about to purchase a boat with Somerhalder before Boone was killed. "It has changed the dynamic, and to say it hasn't is a lie. Before, it was all love and family, and now there's fear. It created a negative thing that wasn't there before. We're all watching our backs now."

SWIMMING FOR HIS LIFE

When Daniel Dae Kim (Jin) decided over the summer that it was time to buy a home on the island — one of the last cast members to do so — he asked producers if he'd be around long enough to warrant such a purchase. In last season's finale, his character was left stranded in the middle of the ocean along with Holloway's Sawyer and Harold Perrineau's Michael.

All they would tell him — as they've told the others — was that the home-buying decision was up to him. "They have to be true to what they do," Kim says.

Perrineau went so far as to enroll in swimming lessons over his summer break in hopes of climbing back on that burning raft and saving his job. Growing up in Brooklyn, Perrineau had bad experiences in the city pool with aggressive cousins who prevented him from keeping his head above water. His daughter, Aurora, 10, had been teaching him a bit, but since early August, he has been working with a coach.

"I can't stay afloat for a long time but enough to wade while they're setting up shots," Perrineau says. "Now, the only thing I have to worry about are the sharks."

He's not kidding. Just after midnight in the dark waters off Makaha Beach, Perrineau is among a second group of "Lost" stars shooting scenes from a different story thread. The still-flaming remnants of the escape raft harbor two of the three stranded characters; one fails to emerge.

The two men lucky enough to make it back onto the raft discover they are being attacked by a great white, as evidenced by three men in wetsuits manipulating a 400-pound mechanical shark on the water's surface. But because of technical difficulties, the shark shot that ultimately was used came courtesy of a crew member holding a fin on a stick. "It was ridiculous," Perrineau says with a laugh.

Left on dry land in the finale, Monaghan remains confident of his job security, based on the international following he brings to the show after appearing in the three "Lord of the Rings" films.

"England, Australia, New Zealand, everywhere I lived, the show's huge," he says matter-of-factly. "It's the biggest (U.S. import) show ever on England's Channel 4. Our agents can argue what we each bring to this show."

Yet he is cognizant that "they're going to have to start killing more of us." The next victim has, in fact, already been notified. Whispers of that unlucky actor's identity leaked to the Mainland in early summer, inspiring a studio publicist to issue a stern warning to the cast and their representatives on remaining tight-lipped.

DOWN THE HATCH

But the biggest secret to date has been what's under the hatch, finally blown open in May's cliffhanger. The mysterious interior, to be explored in the season's first few episodes, was built in a Diamond Head soundstage about a half-hour from the caves.

"I've gone inside (the hatch) now, and I know to some extent what it's about," says the Emmy-nominated Terry O'Quinn, whose character, Locke, was fixated on the hatch for most of last season. "I'm afraid that people are going to be like, 'How can you possibly deliver on such a big promise?'

"But I think it's satisfying. I think it's as good as they could possibly do. They give you an answer within an enigma without giving away the whole balloon. There's a lot of new questions."

Standing near Fox at the base-camp set, O'Quinn is slicing a rope with a razor-sharp knife as his character tells the other survivors he's "going down" into the freshly opened hatch. O'Quinn accidentally cuts his finger, and a medic is called. But the unfazed actor insists on continuing the scene.

"I'm sick of waiting," his character gripes, "for the Others and the brave folks on the raft to come back with help."

Despite the impressive ratings for "Lost" last season, many fans made it clear they, too, were sick of waiting — for answers to the show's many mysteries. Why are they on this island? What is the monster that seemingly was revealed in the season finale to be a shadowy "security system" of sorts? Why did Locke regain his ability to walk after the crash, and why is he struggling again? What is the significance of the number sequence that won Hurley his lottery millions and is etched in the side of the hatch? And, of course, what's in the hatch?

Although that last question will be answered in the premiere, producer Damon Lindelof says the real revelation will come in Episode 3. Lindelof, along with executive producer Carlton Cuse, has been handed the reins now that "Lost" co-creator J.J. Abrams is off shooting "Mission: Impossible 3" with Tom Cruise.

Lindelof says he sat Abrams down to go over an entire season's worth of stories, flashbacks and new characters, all the way through May's season finale.

LOVE FINDS A WAY

Season 2 will find the characters beginning to adjust to their island home and exploring feelings of hope and even passion.

"We've been 40 days on this island dealing with very intense things and not a lot of room for romance," Fox says of the story line. "Anytime people are in extreme circumstances, there has to be moments where people need physical contact and a feeling of being safe."

For Fox's Jack, passion and physical contact likely will present themselves through Michelle Rodriguez ("The Fast and the Furious," "SWAT"), whose new regular character, Ana Lucia, was seen briefly last season in an airport flashback with Jack.

Producers hoped to keep Rodriguez's casting a secret to protect the "big reveal" that a set of new castaways would be discovered along with the rear half of the plane early in the season. But someone leaked the news.

Lindelof confirms that Rodriguez's character will throw a wrench into the Jack-Kate-Sawyer love triangle, and Lilly expects obvious tension to develop between the female characters.

And don't expect a happy blending of the two groups. It will be more like a "Survivor"-esque battle between the tribes.

"Up to now, things have been relatively decent, if you ignore the episode where Sawyer was tortured," Andrews says. "But now things are going to get wild and a lot more violent for everybody. Life will become rather brutal."

And the body count will grow. "The Season 2 cliffhanger," Monaghan hints, "sets it up so that all of us could conceivably die."