The clan attempts to transfer Grace from her human body into her avatar with the aid of the Tree of Souls, but she dies before the process can be completed. Jake finds the refugees at the sacred Tree of Souls and pleads with Mo'at to heal Grace. Pilot Trudy Chacón, disgusted by Quaritch's brutality, frees Jake, Grace, and Norm, and airlifts them to Grace's outpost, but Grace is shot by Quaritch during the escape.To regain the Na'vi's trust, Jake connects his mind to that of Toruk, a dragon-like predator feared and honored by the Na'vi. Mo'at frees Jake and Grace, but they are detached from their avatars and imprisoned by Quaritch's forces. Quaritch's men destroy Hometree, killing Neytiri's father (the clan chief) and many others. Jake confesses to the Na'vi that he was a spy, and they take him and Grace captive. When Quaritch shows a video recording of Jake's attack on the bulldozer to Administrator Parker Selfridge, and another in which Jake admits that the Na'vi will never abandon Hometree, Selfridge orders Hometree destroyed.Despite Grace's argument that destroying Hometree could damage the biological neural network native to Pandora, Selfridge gives Jake and Grace one hour to convince the Na'vi to evacuate before commencing the attack. Soon afterward, Jake reveals his change of allegiance when he attempts to disable a bulldozer that threatens to destroy a sacred Na'vi site. After Jake is initiated into the tribe, he and Neytiri choose each other as mates. Over the following three months, Jake and Neytiri fall in love as Jake grows to sympathize with the natives. When Grace learns of this, she transfers herself, Jake, and Norm to an outpost. Neytiri's mother Mo'at, the clan's spiritual leader, orders her daughter to initiate Jake into their society.Colonel Miles Quaritch, head of RDA's private security force, promises Jake that the company will restore his legs if he gathers information about the Na'vi and the clan's gathering place, a giant tree called Hometree, which stands above the richest deposit of unobtanium in the area.
Witnessing an auspicious sign, she takes him to her clan. Norm Spellman, Jake's avatar is attacked by a thanator and flees into the forest, where he is rescued by Neytiri, a female Na'vi. While escorting the avatars of Grace and fellow scientist Dr. Grace Augustine, head of the Avatar Program, considers Sully an inadequate replacement but accepts his assignment as a bodyguard. Jake Sully, a paraplegic former Marine, replaces his deceased identical twin brother as an operator of one. Pandora, whose atmosphere is poisonous to humans, is inhabited by the Na'vi, a species of 10-foot tall (3.0 m), blue-skinned, sapient humanoids that live in harmony with nature and worship a mother goddess named Eywa.To explore Pandora's biosphere, scientists use Na'vi-human hybrids called "avatars", operated by genetically matched humans. The Resources Development Administration (RDA) mines a valuable mineral unobtanium on Pandora, a densely forested habitable moon orbiting Polyphemus, a fictional gas giant in the Alpha Centauri star system. In 2154, humans have depleted Earth's natural resources, leading to a severe energy crisis.