Plot summary
Claire's mother Carole falls into a coma after a car accident and is visited in the hospital by Christian, who tells Claire that he is her father. Disgusted at being the result of an affair, she tells him to leave. In the present, she realizes that seagulls on the island may be tagged, but Charlie, having been warned by Desmond to avoid fatal situations, refuses to help. Desmond uses his abilities to help her catch a gull and admits the truth about Charlie's inevitable death. She reconciles with Charlie and they attach a note to the gull before setting it free.
Mikhail explains that the Swan's EMP damaged the Others' underwater "Looking Glass" beacon station, meaning their submarine would not be able to return if it left the island. They reach the Others' "sonar fence," and Locke tests Mikhail's claim that is offline by pushing him through it, killing him. The group builds a ladder to climb over the perimeter and makes it to the "Barracks", revealed to be the Others' village, and find Jack living comfortably amongst them.
Credits
Adapted from Wikipedia contributors, Lost season 3. HTML formatting and reference markers removed.