We open on a younger Locke working in a toy store. He plays the board game Mouse Trap with a young customer. He goes over to help a mysterious red-headed woman.
Back on the island Boone and Locke are trying to break into the hatch. Boone asks why Locke has never shared anything from his past; Locke says it would bore him. In an unsuccessful attempt at breaking the glass on the hatch Locke gets stabbed in the leg, but he doesn't feel it at all.
That night at the campfire Locke tests the feeling in his legs. He pricks and burns himself but with no result.
The next day, Boone and Locke discuss how they are next going to attempt to break the glass on the hatch; Locke insists "the island will tell us what to do."
Again, we flashback to the young Locke. He is now chasing the mysterious red-headed women through the store car park. He gets run down by a reversing car but gets back up to catch the woman who tells him she's his mother.
In a coffee shop, Locke and the woman talk. Locke, a child of foster parents, is still not convinced she is his mother. She acts strangely saying that he is special and "part of a design." When Locke asks after his father the woman replies matter-of-factly, "you don't have a father, you were immaculately conceived."
Kate walks in on Sawyer talking to Sun about a plant that's not working. Once he has gone, Sun explains to Kate that Sawyer is suffering from bad headaches. Later that evening Kate asks Jack about headaches and worries there is something seriously wrong with Sawyer. Jack down-plays it and is unconcerned.
Boone is late helping Locke, he is frustrated that they can't break into the hatch and wants to give up. Locke argues that their faith is been tested and that the island will send them a sign. Overhead a small plane falls with a trail of black smoke. Locke suddenly sees the red-headed woman pointing to the sky and Boone covered in blood murmuring "Theresa falls up the stairs, Theresa falls down the stairs" over and over. To his distress, Locke finds himself is back in his wheelchair. Suddenly, Locke wakes up with a fright; it was just a dream, he is still at the camp fire.
We flashback to a young Locke sitting with a private investigator who confirms the red-headed woman - Emily - is his mother, a formally institutionalised schizophrenic. The investigator also has a folder about Locke's father but warns him of the dangers off looking at it. Locke ignores him and goes to see his father - Anthony - who is happy to see him and invites Locke to go hunting.
Back on the island Locke tells Boone of his dream and says he knows where to go now, Boone is sceptical until Locke asks him who Theresa was. They go off to find the plane that Locke dreamed about.
On the beach Michael and Jin are still making a raft. Jack sees Sawyer suffering from a headache. Sawyer admits that his uncle died of a brain tumour and is clearly worried even though he jokes about it.
Boone and Locke continue discussing the dream and looking for the plane. Locke falls over but insists his leg is fine. They find a rosary in a tree, above it a decayed human body.
Flashback to a young Locke going to his father's house where he catches him having dialysis treatment and is told he is in need of a kidney.
Back on the island Boone and Locke see the decayed body is dressed as a priest and has Nigerian money and a gun on it.
Sawyer is irritated by noises on the beach; Kate takes him to Jack who examines him. When the questions get to personal Sawyer storms off. Jack concludes he needs glasses.
Locke stumbles through the trees; Boone realises there's something is wrong with his legs. Locke explains how he was paralyzed before the crash. He is determined to carry on looking for the plane thinking there will be something inside it to help them open the hatch.
A young Locke is hunting with his father, shooting ducks. His father says he is glad they got to know each other whilst they still have time.
Boone carries Locke along. Boone says Theresa was his nanny who fell down the stairs and broke her neck when he was six. Locke sees the plane in the trees overhead and is now convinced that there is something important inside it. He tells Boone to climb up and look inside.
A young Locke is in hospital with his father, preparing to give him a kidney.
Jack approaches Sawyer who is reading on the beach. He tells him he is far sighted so gives him a pair of glasses.
Boone struggles to climb up to the perilously hanging plane. He climbs inside the wreck and sees a map of Nigeria, the plan starts to fall a bit; and there is another dead body in there. He finds a crate-load of Virgin Mary's, inside each statuette are bags of heroin. Locke doesn't understand why there isn't a sign. Boone, frustrated, looks in the cockpit and gets a signal on the radio - he calls mayday as the plane starts to tip off its perch.
Locke screams for him to get out. Someone answers faintly over the radio so Boone gives their flight number just as the plane nose-dives off the cliff. Locke, barley able to walk, stumbles over to find a badly injured Boone pulling him out of the wreck and carrying him to safety.
Kate is thanking Jack for helping Sawyer when suddenly Locke appears with the unconscious and blood-covered Boone. Jack sees he is badly hurt. Locke disappears.
Flashback to young Locke in recovery room of the hospital, the bed beside him is empty. He asks the nurse where his father is. She said that he checked out that afternoon and left no message. Locke's mother appears and confesses that she had set him up on behalf of his father so he could get his kidney. Locke is devastated. He goes to his father's house but is not allowed in. He drives off in a rage and breaks down in tears.
All alone, Locke lies on top of the hatch crying and cursing it. Suddenly a light appears from inside and beams onto his astonished face.