Lost

A sudden plane crash leaves at least 48 survivors stranded on a jungle island, forced to scavenge for survival from the wreckage of the plane. As they get their bearings and pin their hopes on a quick rescue, the band of strangers begin to learn the island holds deep and dark secrets.

Having escaped the "creature" and retrieved the plane transceiver, a group of the survivors travel to higher ground so they can transmit a signal. En route, they receive a mysterious transmission and encounter another of the island's inhabitants. Meanwhile, back at camp, Jack tends to a wounded man who reveals a secret about Kate.

Jack and Hurley discover an alarming secret about Kate, as the marshal's life hangs in the balance and he suffers a lot of pain. Meanwhile Kate, Charlie, Sawyer, Sayid, Boone and Shannon ponder the mysteries they have begun to uncover and worry that telling the other survivors will cause panic. They decide to lie for the time being.

The survivors are jolted awake in the middle of the night when wild island beasts invade the beach encampment. Kate and Michael join the mysterious Locke on a hunt for food-and a shocking secret about Locke is revealed. On the hunt for food someone is injured. Meanwhile, some survivors are horrified by Jack's plan for the dead bodies still scattered among the wreckage-he wants to burn them.

Jack is nearly delirious from lack of sleep and struggles to overcome the haunting events that brought him to Australia and, subsequently, to the island. Meanwhile, Boone gets caught in a treacherous riptide trying to save a woman who went out swimming. A pregnant Claire's health takes a bad turn from lack of fluids, and a thief may have stolen the last bottles of water.

Walt and the others are shocked when Michael is brutally beaten, but only the non-English-speaking Jin and Sun know the truth behind the attack. Meanwhile Kate, Jack, Sawyer and Sayid argue about where the survivors should camp-on the beach, where they're more likely to be seen, or in a remote inland valley where fresh water abounds; and Locke discovers Charlie's secret.

Charlie begins a painful journey of withdrawal from drugs, surprisingly aided by Locke, whose true motive for helping Charlie is a mystery. Meanwhile, survivors struggle to find and free Jack when he's buried alive in a cave collapse, and someone might be secretly thwarting Sayid, Kate, and Boone when they enact a plan to find the source of the French transmission.

Shannon's inhaler runs out and Boone believes Sawyer has the remaining three in his stash. When Sawyer refuses to give them up, Jack and Sayid resort to torturing Sawyer until he agrees to reveal the location of the inhalers. In flashback we hear Sawyer's story and find he is not who he says he is.

Sayid's life is placed in grave danger after he stumbles upon the source of the mysterious French transmission, the woman Danielle Rousseau. She was on the distress call and is found alive. Meanwhile, Hurley has a ridiculous plan to make life on the island a little more civilized. The plan involves golf clubs he finds in the debris, and it looks like it just might work.

Claire has a horribly realistic nightmare about her new baby being harmed or kidnapped. Flashbacks reveal Claire's back-story: the former boyfriend who got her pregnant, then abandoned her, and the psychic who convinced her to take the ill-fated flight that landed her on the island.

Survivors wonder why Charlie and Claire have been abducted - and by whom - and a search party ventures into the treacherous jungle to look for the pair. Suspicions focus on Ethan Rom, who, it was recently discovered, was not a passenger on the doomed flight. Jack battles inner demons relating to his father, while Boone and Locke discover another island mystery.

Jack, Kate and Sawyer fight over possession of a newly discovered locked metal briefcase which might contain insights into Kate's mysterious past. Meanwhile, Sayid asks a reluctant Shannon to translate notes he took from the French woman.

When Locke learns that Boone wants to share their secret with Shannon, Locke decides to teach him a lesson. This leads to Shannon's life being placed in what seems like peril. Boone and Shannon's dark past is revealed in a shocking back story that recalls their relationship right before the plane crash and presages the return of the beast.

Violence ensues and a mysterious island beast makes a re-appearance when Michael and Locke clash over Walt's upbringing. Meanwhile, Charlie is tempted to read the missing Claire's diary, and Sayid enlists Shannon to help decipher the French woman's map.

After the missing Claire returns with no recollection of what has happened since before she boarded the doomed Oceanic flight 815, Jack and Locke formulate a plan of defence against her kidnapper, the mysterious Ethan, who threatens to kill off the other survivors one by one unless Claire is returned to him.

Kate and Sawyer divulge dark secrets to each other while tracking a renegade boar that Sawyer swears is purposely harassing him. Hurley and Sayid worry that Charlie is losing it after facing a brush with death and killing Ethan with 6 bullets to the chest. A shocking prior connection between Sawyer and Jack is revealed in a flashback.

When the raft the survivors have been building mysteriously burns down, Michael is convinced that Jin is responsible for the sabotage, which only serves to escalate their rivalry. Meanwhile, Sun stuns her fellow survivors with a surprising revelation, and Boone gives Sayid a warning about his step-sister Shannon.

When Hurley becomes obsessed with the French woman and heads into the jungle to find her, Jack, Sayid and Charlie have no choice but to follow. Hurley flashes back to the hugely life-altering experience he had before boarding the plane.

Locke thinks he's being sent a sign on how to get the hatch open, and he and Boone venture inland. Jack is reluctant to offer assistance when Sawyer begins to experience excruciating headaches and needs glasses.

Jack tends to a severely wounded Boone after Locke returns him to the caves. In the confusion, Locke slips away to deal with his guilt over the crisis. Meanwhile, Claire unexpectedly goes into labour while deep in the forest.

After another funeral, tempers rise as the survivors' suspicions of each other grow, and an unlikely survivor vows revenge. The events that landed Sayid on Flight 815 play out as he engages Locke in a psychological game of cat and mouse to uncover the truth about the mishap that claimed Boone's life.

Jack suspects foul play when Michael becomes violently ill while building the raft. The suspects include Sawyer and Kate, who compete for the last seat on the raft and do anything possible to prevent each other from getting it. Meanwhile, a secret from Kate's past is revealed to the other survivors on the island.

The Frenchwoman stuns the survivors when she shows up with a dire warning about "The Others,'' while Michael and Jin ready the raft for sailing.

Something unexpected at sea surprises those on the raft; the remaining islanders try to blow open the hatch.

In the thrilling finale to the first season, a visitor to the encampment could be a threat to Claire's infant son.