Kate discovers that someone knows the secret of Aaron's true parental lineage. Meanwhile, the dramatic shifts through time are placing the lives of the remaining island survivors in extreme peril.
Event Year: 2004
Sundown
After recruiting Sayid to his cause, the Man in Black issues an ultimatum to the Others: either join him or die. Meanwhile, Kate is reunited with Claire. In the flash sideways, Sayid helps his brother, who is in debt to a loan shark.
Lighthouse
On Jacob's orders, Hurley leads Jack to a lighthouse. Meanwhile, Claire questions an Other she has captured while tending to an injured Jin. In the flash sideways, Jack is a single father trying to bond with his son.
The Substitute
On the island, the Man in Black attempts to recruit Sawyer in his attempt to leave the island, while an impromptu funeral is held for the real Locke. In the flash sideways, Locke is fired from his job and becomes a substitute teacher.