Season One
The action kicks off with the crash of Oceanic Airlines Flight 815 on a tropical island in which a random polar bear and lethal ‘smoke monster’ reside. The survivors set up camp on the beach and build an escape raft, with surgeon Jack taking charge. Many are haunted by flashbacks, like stepfather-killer Kate, conman Sawyer and the mysterious John Locke - who miraculously regains the ability to walk on the island.
Former Iraqi soldier Sayid encounters an elusive woman called Danielle Rousseau who has lived on the island for 16 years. She warns of some hostile natives called The Others – but it’s too late as they infiltrate the survivor group, destroy the raft and kidnap a young boy called Walt in front of his helpless father Michael. Meanwhile, an underground hatch is discovered....
Season Two
The crash survivors discover the hatch contains electricity, food and a straggly-haired Scot called Desmond whose supposedly world-saving job it is to enter a numerical sequence on a keyboard every 108 minutes. They view some film clips that reveal a scientific group called the Dharma Initiative is behind the hatch and other such stations on the island.
Survivors from the plane’s tail section emerge. Rousseau captures 'Henry Gale', who claims to have crashed on the island but is actually Ben Linus – leader of The Others. In return for being reunited with Walt, Michael works undercover for The Others and leads Jack, Kate and Sawyer (involved in a ‘flirt triangle’) into an ambush. Michael kills Ana Lucia and Libby from the tail section.
The numerical sequence fails to be entered in time, causing a magnetic field to be released. Scientists working for Desmond’s pining fiancée Penelope Widmore pick up this seismic activity from outside of the island.
Season Three
Jack, Kate and Sawyer are held captive by The Others, but the surgeon is needed to operate on a tumour in Linus’s spine – and secures the release of his two cellmates. Jack hits it off with an Other called Juliet. Through flashbacks, Desmond’s turbulent past with his fiancée’s affluent father Charles Widmore is revealed. He also experiences visions of British musician Charlie, now romantically involved with pregnant fellow survivor Claire, perishing in various accidents and frequently prevents such scenarios.
The Smoke Monster kills the spiritual Mr Eko from the tail section. Jack and Juliet plan to escape from the island in a submarine, but Locke blows it up in the belief that they must not tamper with fate. Juliet tells pregnant survivor Sun (who is married to Jin despite his acrimony with her father) that there are massive complications involved with giving birth on the island.
Naomi parachutes onto the island and claims to be from Penelope’s rescue mission, but Charlie dies in an underwater station trying to unblock the signal so she can contact her freighter. Linus takes Locke to meet the unseen, supernatural leader of The Others called Jacob. Ben subsequently shoots Locke, who awakes to a vision of Walt telling him that those on the freighter are going to kill everyone.
