Question: Who are the Others?
The idea of the Others was first introduced in episode 1x9, Solitary.
Answer: Sayid finds a French woman, who lives in a bunker on the island. She tells him about "the Others". She hears them whispering, but she's never seen them. The Others are very powerful and very sneaky and are believed to have taken several of the Tailies. They also took Claire, but she later escaped.
The Others are seen living in a nice neighborhood on the island and capture Jack, Sawyer, and Kate (Ep: 3x1, A Tale of Two Cities).
Their leader may be the mysterious Ben.
The Others keep Kate and Sawyer captive in cages outside. Jack is held in the Hydra. Jack gets the upper hand when he does spinal surgery on Ben and makes it possible for Sawyer and Kate to escape.
Later, Jack and Juliet escape.
Ben was originally a member of Dharma, but helped the Others to wipe out Dharma (Ep: 3x20, The Man Behind the Curtain).
Many of the Others were killed in an attack on the Flight 815 survivors (Ep: 3x22, Through the Looking Glass).
Learn more about individual Others.
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