Lost (season 6)
The spirit of Jacob asks who among them would become Protector of the island, and Jack volunteers. At the waterfall cave, Jack drinks the water of immortality and returns to the group. Jack says they must meet with Locke and Desmond to settle the dispute and kill Locke. The 2 groups meet on the hilltop, and just the 3 proceed toward the waterfall cave. There, Desmond descends on a rope into the cave, but pulls a rock from the bottom, which puts out the light of the power source. The island begins a series of earthquake tremors, to fall into the sea, with rocks tumbling into the water. Locke flees the area, now needing to get the sailboat to the other island: he has lost his immortality when the light source was put out. Jack chases him to the sea cliffs to stop him from leaving, and a long fight begins. Locke grabs a knife and stabs Jack in the side, then forces the knife up to Jack's neck. Before plunging the knife, a gunshot is heard: Kate as promised, has shot Locke (the Smoke Monster) in the back, and Jack pushes him off the sea cliff, to die on the rocks below.Jack tells them he must return to the island core, as he promised Jacob, to restore the light at the waterfall cave. He instructs Kate to leave with Sawyer to get Claire into the airplane on the other island. Kate in turmoil kisses Jack goodbye, fearing it will be the last time. Kate and Sawyer jump into the sea and swim to the sailboat at anchor.Hurley and Ben help Jack return to the waterfall cave. They lower Jack into the cave, where he revives and ties Desmond to the rope. Jack then puts the missing stone back into the floor, and restarts the light power source. When Hurley and Ben pull the rope, they find only Desmond. They call below, but Jack, overcome by the knife wound and rushing water, never answered, so they take Desmond away from the area. Some time later, Jack awakens, alone, outside the cave, as if lifted from the depth of the cave by an unseen force. Dazed, he wanders through the jungle, but he is losing strength. Just as with Locke's death, Jack also lost his immortality, and protection, at the first time the light source was put out. Jack falls to the ground, looking up to the blue sky. At that point, he sees Kate's plane flying far overhead, and then closes his eyes, for the last time.