Their plan having apparently failed, Sawyer tries to save Juliet when the survivors find themselves back at the hatch site. Elsewhere, Oceanic Flight 815 prepares to land in Los Angeles.
Hurley leads his friends to the Temple, where he believes the Others can save Sayid's life. In L.A., Kate attempts to escape from the marshal's custody.
While attempting to escape the marshal's custody, Kate finds herself entangled with Claire's. Jack must decide whether to trust the Others and put Sayid's life at risk once again.
Locke attempts to recruit new followers on the island, promising answers to Sawyer. Off the island, John faces the challenges of an ordinary life as a handicapped man.
On directions from Jacob, Hurley leads Jack through the jungle on a secret mission -- while on the mainland, Jack deals with unforeseen family issues. Jin must decide whether he can trust Claire when she takes one of the Others captive.
Benjamin Linus executes a coup to steal the school principal's job, and must decide where his priorities lie. On the island, Ilana holds Ben responsible for his crime against Jacob, and Richard seeks Jack's help for a difficult task.
Locke sends a skeptical Sawyer to Hydra Island on a recon mission. In a very different life, James uses his position as a police detective to hunt the man he blames for his parents' deaths.
Jin and Sun try to cover up an illicit affair when her father's business associate comes looking for his payment. Sun must decide who to trust as she seeks to be reunited with her husband, and Locke travels to Hydra Island.
Charles Widmore subjects Desmond to a high-powered experiment, putting his life on the line. Elsewhere Desmond encounters Charlie Pace, a junkie rock star who is convinced there is more to life than what they know.
A ghost from the past urges Hurley to stop his friends from destroying the plane, while in another life Hugo seeks the one thing he doesn't have -- love. But the woman who catches his eye claims to have already known him in another life.
Jack must decide whether to trust the man posing as John Locke, or join his friends in leaving him. Locke sends Sayid to kill Desmond, while in Los Angeles, Jack and Claire's paths cross again.
When Whidmore captures Sawyer and the others, Jack joins Locke in a plan to rescue them and escape the island. In L.A., Dr. Sheppard presses Locke to allow him to perform surgery that could allow him to walk again.
Far in the island's past, a mysterious woman raises a pair of boys in the hopes that one of them will one day take her place. But Jacob's brother has desires of his own.
Jack's group sets out in search of Desmond, but finds Jacob waiting -- with answers. Ben finds himself between Locke and Whidmore, and Desmond begins to assemble the Oceanic 815 passengers.
Jack and Locke draw closer to their final showdown, agreeing to take Desmond to the heart of the island -- with different beliefs about what will happen. In another life, Desmond and Hugo help their friends remember.
Jack discovers a way the Smoke Monster can be killed, though it puts the island and everyone they love at risk. In Los Angeles friends new and old make their way to the concert, and to new revelations about their final destiny.
