From the big moments to the big let-downs, we look at the highs and lows of the show's six seasons

By EW Staff
May 07, 2010 at 04:00 AM EDT

Season 1
A plane crashes on a tropical island populated by poplar bears, a scary smoke monster, and even scarier people

Best Episode ”Walkabout” (Airdate: Oct. 13, 2004) John Locke hunts boar and meets the Smoke Monster. And before the crash…he was in a wheelchair!

Worst Episode ”Whatever the Case May Be” (Jan. 5, 2005) WHAT’S IN THE CASE?! WHAT’S IN THE CASE?! Oh. It’s a toy airplane.

Once the surviving passengers of Oceanic Flight 815 cleaned off the blood and sand from their horrific crash landing on a South Pacific island, their traumatic journey truly began. Our disparate group of castaways, led by spinal surgeon Jack Shephard, discovered that help wasn’t coming for them (WTF? A 16-year-old looped distress signal in French?), but some kind of monster was. And the waves of weird kept washing ashore. Why is Jack seeing visions of his dead father? Why are Hurley’s lottery numbers popping up on the Island? Why are the Others, those creepy Islanders, trying to abduct pregnant Claire? Who’s this crazy lady claiming that the Others stole her baby? For every secret born of the Island, there was a flashback-framed mystery tucked into the pocket of one of our characters. Why was Kate running from the law? What painful truth was contained in Sawyer’s letter? And why is John Locke growing stronger and wiser? Much of the drama revolved around the castaways’ struggles to build a life on this cursed patch of paradise while figuring out a way to escape it (Oh no, someone torched the raft!). In the finale, we felt a chill as the Others snatched Walt (”We’re going to have to take the boy”) and a rush of wonder as the castaways blew open the mystery hatch with dynamite from the Black Rock ship marooned in the jungle. The reveal? A broken ladder leading down into…gotta wait till next season? C’mon!

Biggest Revelation The monster! The Hatch! The numbers! The Others! Take your pick.

Moment That Tested Our Faith There’s shrewd stalling. Then there’s Claire’s amnesia.

Season 1 MVP Jack Shephard
From the moment the series began, with that first image of Jack’s opening eye, we looked to the good doctor to take charge. Whether this daddy-issues-laden soul wanted the job was another question. Still, when it came time to go fist to fist with an Other or set up a makeshift trauma room to try to save one of his own, Jack was the guy (at least in season 1) you most wanted on your side.

Season Grade A — Dan Snierson

Season 2
So who are these tailies? Plus: Numbers, numbers everywhere, and the introduction of one formidable foe — Flight 815 survivors, meet Benjamin Linus

Best Episode ”Man of Science, Man of Faith” (Sept. 21, 2005) This premiere ep goes down the much-discussed Hatch.

Worst Episode ”Adrift” (Sept. 28, 2005) A flashback to (yawn) Michael’s custody battle, and a huge letdown after the premiere.

After blowing open the Hatch and finding a guy named Desmond living inside, the survivors began unraveling the much larger enigma beneath that door in the jungle floor: the Dharma Initiative. This communal research project dating back to the 1970s seemed to encompass a broad swath of scientific disciplines, from psychology to electromagnetism to zoology, according to training films in the Hatch. More specifically, Dharma had Desmond convinced he must enter the magic numbers — 4, 8, 15, 16, 23, 42 — into a computer every 108 minutes to stop the station from blowing up. Whether or not this was truly necessary was the subject of much faith-versus-reason debate for John Locke. Turned out (oops!) it was necessary — which we found out after the thing blew to bits in the finale.

Of course, along the way, there were complications on all fronts. The original survivors reunited with the tail-section passengers, who’d been fighting for their own existence across the Island under the leadership of scrappy ex-cop Ana Lucia. The merging of the tribes brought some good (drug dealer-turned-priest Mr. Eko; Rose’s long-lost husband, Bernard), some bad (Shannon was accidentally shot by Ana Lucia), and some debatable (the relatively useless Libby). The Others were a confusing threat (what was with all the swiping of kids and sneaking around the jungle?) — led by a shifty guy named Ben Linus, who first identified himself as waylaid ballooner Henry Gale. The mind games came to a head when the Others manipulated Michael into shooting Ana Lucia and Libby, then bringing Jack, Kate, Sawyer, and Hurley to their camp under the guise of ”rescuing” Walt. By season’s end, Walt and Michael were sailing off to safety; the Others were holding Jack, Kate, and Sawyer prisoner; and Hurley was set free to report back to his fellow survivors.

Biggest Revelation A finale scene in which scientists in a far-off research station located the Island for Penny Widmore, Desmond’s onetime ladylove.

Moment that Tested Our Faith When Ana Lucia died, and we barely cared.

Season 2 MVP Benjamin Linus
The first hint of what this Island was really about came in the form of ”Henry Gale,” a.k.a. Ben posing as a marooned hot-air-balloon pilot — and morphing into a slippery villain who’d make the survivors look back on their harrowing plane crash as the good old days.

Season Grade A- — Jennifer Armstrong

Season 3
Kate and Sawyer do the horizontal mambo (make that vertical mambo) in a polar-bear cage, Smokey kills, Charlie dies, and then everything changes: flash-forwards?!?

Best Episode ”Through the Looking Glass” (May 23, 2007) The game-changing finale capped an awesome stretch that saved Lost from becoming a phenom-imploding cautionary tale.

Worst Episode ”Stranger in a Strange Land” (Feb. 21, 2007) Flashbacks about Jack’s tattoos? Proof that Lost needed an end date.

It was the season that pitted the castaways against the Others — and Lost against its fans. The fake Henry Gale was revealed to be Benjamin Linus, an ex-Dharma dude who gassed his own people (and his bad dad) to impress the Others and their ageless steward, Richard Alpert. Ben’s season-long scheme: to remedy the Others’ inexplicable inability to reproduce by abducting the castaway women. His co-conspirator in the effort was Juliet, a brilliant fertility doctor who fell for Jack and switched teams. Meanwhile, Locke, Desmond, and Mr. Eko survived the Hatch explosion — but Mr. Eko was felled by Smokey, and Desmond began seeing prophetic flashes of Charlie’s death. Desmond’s dilemma: Save Charlie — or let him die to fulfill a future that would bring Penny to the Island? Meanwhile, Sawyer and Kate got carnal in a polar-bear cage at an old Dharma station. Weird-sexy! In a flashback, Jack got carnal with Bai Ling in Thailand. Crappy — not sexy! Nikki and Paulo appeared, then died. Whatever! Oh, and Sun learned that sperm-challenged Jin knocked her up after all. (Whew!) Egged on by Alpert to usurp Ben as King Other, Locke tried to prove himself by getting Sawyer to kill his father, Anthony Cooper. Locke’s prize: a brief meeting with Jacob’s alleged ghost — and a gunshot to the gut by jealous Ben. Jack foiled Ben’s seize-the-dames gambit, then hailed Penny’s freighter to the Island — except as Charlie learned moments before his heroic death, the freighter wasn’t Penny’s ship. Then, the brain-pocalypse: a flash-forward twist ending. Jack and Kate escaped the Island!? Jack’s a junkie!? Jack wants to go back to the Island!?

Biggest Revelation How did Locke become a paraplegic? Anthony Cooper threw him out a window! Who swindled Sawyer’s parents? Cooper, too!

Moment that Tested Our Faith Two words: Hydra station. Actually, two more words: Nikki, Paulo. Wait! Two more: Bai Ling.

Season 3 MVP Charlie Pace
The heroin-hooked, Claire-smitten rocker seemed tapped out as a character. Then the Island singled him out for extinction and Charlie was suddenly reborn as a courageous existential hero. His sacrificial death remains Lost‘s most heartbreaking moment.

Season Grade B — Jeff Jensen

Season 4
Turns out life off the Island isn’t as great as the Oceanic Six thought it would be. And who are these freighter folks and why are they causing so much trouble?

Best Episode ”The Constant” (Feb. 28, 2008) Desmond’s mind jumps through time, until a call to Penny helps center him. Sniff.

Worst Episode ”The Other Woman” (March 6, 2008) Such a hussy, that Juliet. Has an affair. Spurns Ben. Kisses Jack. Snooze.

With Charles Widmore’s freighter firmly anchored off the Island, our castaways had never been more divided: Those siding with Jack believed the boat would deliver them from their Island hell, and those with Locke feared it would bring certain doom.

Turned out both camps were right. Flash-forwards into the future revealed only a half dozen of the Oceanic Flight 815 survivors ultimately made it off the Island. Stranger still, this ”Oceanic Six” told the world they were the only survivors, and that lie propelled them into some not-so-happy places. Jack turned to pills and booze; Kate tried to raise Claire’s son, Aaron, as her own; Hurley checked back into the loony bin after dead people started talking to him; believing Jin dead, Sun gave birth to their daughter, Ji Yeon, alone; and Sayid became an assassin for — wait, Ben?!

Back on the present-day Island, people had reached their limits, and things came thrillingly, tragically undone. Ben tried to work his wily mojo on a team of mercenaries from the freighter, only to watch them execute his adopted daughter, Alex. Locke decamped with his crew to New Otherton, awaiting guidance from the Island that never came. And as Jack watched his friends second-guess his leadership, his own body rebelled against him, forcing Juliet to perform a gross emergency appendectomy.

Sacrifices abounded. Fractured and frightened, the castaways scrambled to get to the freighter, only to discover a massive load of C4 explosives; the boat exploded, with Jin still aboard. Sawyer leaped from a fuel-starved chopper so Jack, Kate, Hurley, Sun, Sayid, and Aaron could escape. (They did, and agreed to lie to protect their friends still on the Island.) And seemingly on instructions from unseen Island guru Jacob, Ben volunteered to turn a frozen donkey wheel deep underground, which banished him from his beloved home and ushered in the season’s…

Biggest Revelation The Island can be moved.

Moment that Tested Our Faith Michael returned! Sorta helped out! And then blew up? Okay, then!

Season 4 MVP Desmond Hume
It may have been for just one episode, but Desmond’s hopscotch through time to reach his love Penny — equal parts head-squeezing sci-fi and heartrending romance — elevated the character to a class all his own, and embodied the show at its absolute best.

Season Grade B+ — Adam B. Vary

Season 5
Jack and Co. return to the Island. Time traveling causes headaches — and nosebleeds. And seriously, how adorable are Sawyer and Juliet?

Best Episode ”The Life and Death of Jeremy Bentham” (Feb. 25, 2009) The scene of Locke’s death = Lost‘s finest acting moment.

Worst Episode ”The Lie” (Jan. 21, 2009) Not ”bad” — Hurley’s summary-of-Lost soliloquy was genius — just a weak effort in a solid year.

This was the season that Lost really let its geek flag fly. It began with the Island breaking loose from the grooves of reality and the Left Behinders time-traveling randomly through Island history (see sidebar). Along the way, Charlotte’s brain melted in a series of nasty nosebleeds. John Locke ended the quantum crisis by cranking the donkey wheel and parking his friends in the 1970s Dharma compound. From there, the chief villains of the Lost saga took control. Charles Widmore and Eloise Hawking — ex-lovers, former leaders of the Others, and Daniel Faraday’s parents — maneuvered the Oceanic adults (plus Ben and Frank Lapidus) back to the Island on Ajira Flight 316, with Locke’s corpse in tow. (Shocker! Off the Island, a jealous Ben had murdered him.) Via mysterious magic, Jack, Kate, Hurley, and Sayid landed in the Dharma days. Shocker! Sawyer and Juliet had fallen in love and were playing house! Meanwhile, Lapidus, Sun, and Ben ended up in 2007. Shocker! Locke was alive!? Nah. He was actually a shape-shifting Island entity bent on manipulating Ben into killing the elusive and seemingly saintly Jacob, who had touched various castaways at key moments in their lives. Fun Jacob Facts! He was served by an off-Island cult of zealots led by sexy soldier Ilana, who also crashed on the Ajira flight. He lived within the remains of the Statue, which used to be a towering edifice modeled after an Egyptian fertility goddess. Back in 1977, the castaways attempted to save themselves by altering history, with mixed results. Sayid tried to murder young Ben. Fail! Queen Other Eloise Hawking, pregnant with Faraday, killed adult Faraday — a tragedy she had hoped her son would figure out how to avert. Fail! Jack — who returned to the Island a man of faith in search of his destiny — became convinced that his purpose was to change the future by detonating a hydrogen bomb at the Hatch site, a volatile spring of electromagnetic energy. After falling into the work site, and with what seemed to be her dying breath, Juliet banged on the bomb to make it explode. Fail?

Biggest Revelation Is all of Lost simply a cosmic backgammon match between the idealistic Jacob and the cynical Man in Black? Looks like it.

Moment that Tested Our Faith As if she stepped out of a Harry Potter movie, Ms. Hawking hammily expounded on the Island and its mystical hoo-ha and left us wondering: Maybe it would be cooler if Lost didn’t explain its mysteries.

Season 5 MVPs Juliet and Sawyer
Season 5 was a nerdy delight, but it didn’t find its heart until Lost forged its most surprising romantic union ever. Sawyer blossomed with redemption, and an underutilized Juliet found new purpose. Then she later died. We’re still crying. Sorry, Skaters: Sawliet Rules!

Season Grade B+ — JJ

Season 5: A Chronology

With all the time-jumping this season, the Island dwellers weren’t the only confused folk. We put the events in their proper order.

The time travelers see the Statue’s butt. (It’s the Egyptian goddess Taweret!)

Daniel Faraday helps Richard and the Others fix their leaking H-bomb problem.

The time travelers finally stop time-jumping and join the Dharma Initiative. But we’re getting ahead of ourselves…

Circa 1977
Jack, Kate, Hurley, and Sayid land in the Dharma past. Then they blow up Jughead.

Jin is found by pregnant Rousseau and her scientist friends. Montand gets dismembered by Smokey.

Locke is shot by Ethan after nearly getting struck by the crashing plane carrying Mr. Eko’s dead brother. Welcome to Danger Island!

2001 — 02
Faraday tries to send a message to Desmond in the future via Desmond in the past. (We didn’t understand that one either.)

Season 1 revisited: Locke sees the Hatch light up; Sawyer spies on Aaron’s birth.

Circa 2007
Richard tells Locke he must bring the Oceanic Six back to the Island — and that he must die to do it. Sucker! — JJ

Season 6
Juliet detonates jughead. Everyone leads double lives. The temple is introduced and destroyed. (Yeah!) Plus Fake Locke is one killer dude — make that monster. (RIP: Sayid, Sun, and Jin.)

Best Sideways Story Desmond, the brutal, romantic super-Buddha. Assist to Charlie for reactivating Des with magnetic cool.

Worst Sideways Story Fugitive Kate. The least developed of the tales and the least different from Island-world mythology.

The explosion of Jughead changed nothing. The explosion may have changed everything. Huh? This season has seemingly explored both options, creating two shows in one. In the parallel world, Oceanic 815 never crashed and the passengers have different lives. Jack’s a divorced father. Locke is engaged to Helen. Sawyer’s a cop. Jin and Sun are secretly dating. Sayid ”translates contracts,” whatever that means. Ben is…a schoolteacher?! The Sideways world took a turn when Desmond — right-hand man to Charles Widmore — began remembering his Island life after a near-death experience facilitated by a similarly enlightened Charlie. Desmond is now trying to get all his old Island friends to recall their castaway selves. Will he succeed in his mission? And what do these awakenings really mean? We’ll see. Meanwhile, in the Jughead-changed-nothing world, the castaways were transported to the present-day Island and sought refuge inside the Temple, at least until Fake Locke got Born-Again-Bad Sayid to kill its guardians, allowing him to ransack the Island’s sacred heart. Fake Locke’s mission: to kill Jacob’s potential replacements (Jack, Sayid, Sawyer, Hurley, and the Kwons) so he can escape the Island. Dead so far: Jin, Sun, and Sayid. Though Fake Locke has our heroes on the run, he does have another enemy to contend with: Charles Widmore, who returned to the Island along with a new Zen Desmond. What’s Widmore’s grand purpose in the Island endgame? What’s the backstory on the Jacob/Man in Black rivalry? And what’s the final fate of the castaways? The end of Lost shall make all things clear — or so we hope.

Biggest Revelation So Far Tough to call. That the whispers are spirits of the Island dead? That Jacob conspired to bring the castaways to the Island to groom his replacement? That the mysterious numbers correlate to Jacob’s candidates? That the Island is a ”cork” holding in the ultimate evil? In a close race, we cast our vote for the revelation that the Monster = Man in Black = Fake Locke.

Season 6 MVP John Locke
This season brought us the Locke-ness Monster, a.k.a. Fake Locke or the UnLocke. Lost needed a supreme übervillain to help pull together its disparate mysteries and conspiracies, and it accomplished the mission perfectly with this character, played with commanding charisma by Terry O’Quinn.

Season-to-date Grade B+… but a strong finish can bump this up to a solid A. — JJ