Contains spoilers for this episode and earlier episodes.
Locke returns during Boone's funeral and describes the aircraft accident, but Jack attacks him and demands the truth. Exhausted and weakened by the transfusion, Jack refuses to rest until Kate secretly drugs his drink. Shannon asks Sayid to deal with Locke for her. Sayid questions Locke during a walk to the wrecked plane, learning that Locke was the person who struck him while he was trying to locate the French distress signal.
Flashbacks show intelligence officers recruiting Sayid to infiltrate a terrorist group in Sydney by offering information about Nadia. His former friend Essam belongs to the group. Sayid tries to spare him, but the officers insist that Essam proceed far enough with the planned bombing to reveal the stolen explosives. When Sayid finally discloses his cooperation, Essam kills himself. Sayid then postpones his flight to California so he can claim his friend's body and arrange a burial.
On the island, Sayid concludes that Locke did not intend Boone's death and refuses Shannon's request for revenge. She takes a gun and confronts Locke herself. Sayid tackles her as she fires, leaving Locke with a graze to his head. Separately, Charlie discovers that Sawyer's voice quiets Claire's baby and gets him to read aloud. Later, Sayid tells Locke that he protected him because he may help them survive, then insists that Locke show him the hatch.