Pilot: Part 1 EPISODE 1
The survivors of a plane crash have to get over the accident and collaborate to stay alive in a dangerous, mysterious island in South Pacific.

Pilot: Part 2 EPISODE 2
As Jack, Kate and Charlie return from their little "trip", Sayid is trying to fix the radio. He goes together with Kate, Boone, Sawyer, Shannon and Charlie to find a high place so the radio will work... and in the way they have a meeting with a little island "magic" being. Meanwhile, back at beach, Jack tries to help the US marshal, and some more secrets are revealed... some who include Charlie's drugs and Kate's handcuffs.

Tabula Rasa EPISODE 3
Kate, Charlie, Sawyer, Sayid, Boone and Shannon decide to keep the French transmission a secret from the other castaways not to alarm or panic them. Meanwhile, back at beach, Jack and Hurley find an incriminating mug-shot paper of Kate. A flashback to Kate's origins show the reason for her being in Australia: she was fugitive from the USA and stayed with a local farmer who turned her into the US Federal Marshall Mars whom was tracking her down. Also, Michael is disturbed by the friendship becoming between the weird-minded Locke and his son Walt who agrees to help Walt find his missing dog, Vincent.

Walkabout EPISODE 4
After wild boars raid the beach camp in the middle of the night, the survivors find that they do not have any food and John Locke organizes a peccary hunting with Kate and Michael. Locke's background story reveals why he came to Australia on a spiritual retreat, and a miracle that happened to him after the crash. Meanwhile, Sayid builds some antennas, trying to locate the source of transmission of the French distress signal, and Kate offers to install them. Also, Jack decides to burn the bodies in the fuselage since they are attracting wild animals to the survivor's base, and Claire wants to make the eulogy for the survivors. Jack also talks to Rose, another survivor, about her depression over this current situation.

White Rabbit EPISODE 5
Jack sees his father on the island, and goes searching after him- and after a source of water. back at beach, Claire faints and the few bottles of water that were left are gone. Who took them? Sawyer? Jin?

House Of The Risng Sun EPISODE 6
Troubles escalate when Jin attacks Micheal for no reason. Soon, another secret is revealed when Sun reveals to Michael that she actually speaks English and is afraid of her controlling and jealous husband. Meanwhile, Jack goes with Kate, Locke and Charlie to the water source, and comes up with an idea: to move all the castaways into the caves. Jack and Sawyer try to convince Kate to move into their side. Also, Locke finds out about Charlie's heroin addiction.

The Moth EPISODE 7
Charlie Pace is obliged by John Locke to stay clean and feels the effect. Meanwhile, Sayid Jarrah, Kate Austen and James "Sawyer" Ford tries to triangulate the French distress signal through antennas to find where the transmission source is located. When the cave collapses burying Jack, Charlie rescues him and win his inner battle against the drugs.

Confidence Man EPISODE 8
Shannon his having an asthma attack, and Boone is sure that Sawyer has her medications- but he won't give it. As Kate's way to deal with this situation doesn't work, Sayid takes things into his own hands... and IT WILL NOT end good.

Solitary EPISODE 9
Ashamed with his behavior torturing Sawyer, Sayid Jarrah decides to leave the group of survivors and travel alone through the island, trying to find the source of transmission and map the place. He is arrested and tortured by the French survivor Danielle Rousseau (Mira Furlan) and recalls his beloved Nadia (Andrea Gabriel) back to his days years earlier in Iraq as part of the interrogation/torturer for the Republican Guard. Meanwhile, Hurley decides to get the survivors spirits up by getting up a golf course in a sunny field.

Raised By Another EPISODE 10
Claire begins to have reoccurring nightmares which one night result in her turning up with bloody hands, which leads Charlie to find out what is really going on. However, Jack isn't sure that anything really happened. Meanwhile, Hurley finds the flight manifest and discovers something shocking about a certain passenger.

All The Best Cowboys Have Daddy Issues EPISODE 11
Jack, Kate, Locke and Boone go after Ethan, Claire and Charlie. They separate, and while Jack and Kate confront Ethan, Locke and Boon find another mystery at the jungle. Flashbacks reveal more about Jack's past with his dad.

Whatever The Case May Be EPISODE 12
Kate and Sawyer discover a briefcase and the race begins to win ownership of it. Charlie is still depressed over Claire, and is given a sharp talking to by Rose.

Hearts And Minds EPISODE 13
Boone Carlyle is jealous of Sayid Jarrah, because he becomes close to his half-sister Shannon Rutherford. Boone tells John Locke that he wants to reveal the secret about the hatch in the woods to Shannon. Locke hits Boone, heals his head with a medicine and fastens him with a rope in a tree, living him alone in the forest. Boone's background story reveals his complicated relationship with the irresponsible Shannon, and about why he ventured to Australia to rescue her from a bad relationship, while in the present he tries to save her from the unseen forest creature. Meanwhile, Kate questions Sun's behavior and learns that she can speak English, while Hurley faces the language barrier to repay Jin for teaching him how to fish.

Special EPISODE 14
John Locke is teaching Walt Lloyd to throw knives, and Michael Dawson feels jealous with the situation. He forbids Walt to meet Locke, and recalls his romance with Walt's mother Susan Lloyd (Tamara Taylor), a overachieving executive who took the infant Walt away, and Michael having an awkward reunion 10 years later with the uncertain and spoiled Walt in Australia. Walt becomes upset with the situation and decides to hike with his dog Vincent into the woods. At the end, Locke and Boone Carlyle find Claire Littleton wandering in the forest.

Homecoming EPISODE 15
After the missing Claire returns with no recollection of what has happened since before the doomed flight of Oceanic 815, Jack and Locke formulate a plan of defense against her kidnapper, the mysterious Ethan Rom, who threatens to kill off the other survivors unless Claire is returned to him. Meanwhile, the disappointment Charlie feels when Claire does not remember him triggers recollections of Lucy, a woman he had let down in the past back in England where Charlie ruined their engagement so he could steal money from her to fuel his escalating heroin addition.

Outlaws EPISODE 16
James "Sawyer" Ford wakes up from a nightmare with a boar inside his tent. He finds his canvas in the woods, but is attacked by the animal. He decides to chase the boar with Kate Austen following its track in the forest. Along their hunting, Sawyer recalls his dark past since he was a child until his final revenge against the con man that destroyed his family.

...In Translation EPISODE 17
When Jin Kwon is having a serious quarrel with his wife Sun Kwon, Michael Dawson defends her. Later, when Michael's raft is set afire and Jin has his arms injured by heat, Michael and Sawyer blame him for the incident. Sun finally reveals her secret when she speaks in English to defend her husband and he feels ashamed leaving her. Jin recalls how his love for Sun was destroyed by her evil and unscrupulous father.

Numbers EPISODE 18
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. Meanwhile, Locke asks Claire to help build a mysterious item.

Deus Ex Machina EPISODE 19
Locke begins to suffer physical difficulties as he and Boone try to find a way into the hatch; Jack is reluctant to offer assistance when Sawyer begins to experience excruciating headaches.

Do No Harm EPISODE 20
Claire goes into labor while a helpless Charlie goes into panic mode. Meanwhile Locke is missing, Jack tends to a wounded survivor and Sayid presents Shannon with a romantic surprise.

The Greater Good EPISODE 21
After burying one of their own, tempers flare as the castaways' suspicions of each other grow -- and an unlikely survivor vows revenge. Meanwhile, Claire and Charlie struggle to calm her newborn.

Born To Run EPISODE 22
Jack suspects foul play when Michael becomes violently ill while building the raft. Meanwhile a secret from Kate's past is revealed, the mysterious hatch is shown to a few of the survivors, and Walt gives Locke a warning.

Exodus Part 1 EPISODE 23
The French woman -- Rousseau -- shocks the survivors by showing up with a dire warning about "the others." Meanwhile, Michael and Jin ready the raft for sailing.

Exodus Part 2 EPISODE 24
The castaways on the raft are surprised at sea by something unexpected. Meanwhile, remaining islanders attempt to blow open the hatch, and a visitor to the encampment might be a threat to Claire's infant son.