Plot summary
Against Christian Shephard's advice, Jack, bolstered by his success with Sarah, operates on a man with a spinal tumor, who dies during the procedure. His daughter kisses Jack and he admits this to Sarah, who has already planned to leave him and makes it official. In the present, Michael steals guns from the Swan and goes off alone to find Walt. Jack, Locke, and Sawyer go after him and encounter a group of Others led by Tom Friendly, the man who took Walt. He confirms that "this is our island" and reveals that they have Kate, who had followed the trio. The group surrender their weapons for Kate's safety. When they return to the beach, Jack asks Ana Lucia about training an army.
Credits
Adapted from Wikipedia contributors, Lost season 2. HTML formatting and reference markers removed.