Introduction(for people who didn't watch eragon series before) (copy online)

A shade named Durza, along with a group of urgals, ambushes a party of three elves. After he and the urgals kill the other elves, Durza attempts to steal an egg carried by one of the female elves, but is foiled when she causes it to vanish. Infuriated, he renders her unconscious with a ball of fire and abducts her.

Eragon is a fifteen-year-old boy who has lived with his uncle Garrow and cousin Roran on a farm near the village of Carvahall, ever since his mother Selena, Garrow's sister, left him there right after his birth. While hunting in the Spine, Eragon is surprised to see the blue dragon egg, which he believes to be a stone, appear in front of him. A few months later, Eragon witnesses a baby dragon hatch from the egg. Eragon names the dragon Saphira, after a name the old village storyteller Brom mentions. He raises the dragon in secret until two of King Galbatorix's servants, the Ra'zac, come to Carvahall. Eragon and Saphira manage to escape by hiding in the Spine, but Garrow is fatally wounded and the house and farm are burned down by the Ra'zac. Once Garrow dies, Eragon is left with no reason to stay in Carvahall, so he goes after the Ra'zac with his newly hatched dragon, seeking vengeance for the destruction of his home and his uncle's death. He is accompanied by Brom, who provides Eragon with the sword Zar'roc and insists on helping him and Saphira.

Eragon becomes a Dragon Rider, an ancient warrior charged with promoting peace in Alagaësia, through his bond with Saphira. He is the only known Rider in Alagaësia other than King Galbatorix, who, with the help of the now-dead Forsworn, a group of thirteen dragon riders loyal to Galbatorix, killed every other Rider a hundred years ago. On the journey, Brom teaches Eragon sword fighting, magic, the ancient elvish language, and the ways of the Dragon Riders. Their travels bring them to the city of Teirm, where they meet with Brom's friend Jeod. Eragon's fortune is told by the witch Angela, and her companion, the werecat Solembum, gives Eragon some mysterious advice. With Jeod's help, they are able to track the Ra'zac to the southern city of Dras-Leona. Although they manage to infiltrate the city, Eragon encounters the Ra'zac in a cathedral and he and Brom are forced to flee. Later that night, their camp is ambushed by the Ra'zac. A stranger named Murtagh rescues them, but Brom is mortally wounded. Saphira watches over Brom as the night progresses, yet when morning comes they realize there is nothing they can do to save him. Brom gives Eragon his blessing, reveals that he was also once a Dragon Rider and that his dragon's name was Saphira, and dies. Saphira then encases Brom in a tomb made of diamond.

Murtagh becomes Eragon's new companion and they travel to the city Gil'ead to find information on how to find the Varden, a group of rebels who want to see the downfall of Galbatorix. While stopping near Gil'ead, Eragon is captured and imprisoned in the same jail that holds a woman he has been having dreams about. As she is being dragged past she is revealed as an elf when her pointed ears are uncovered. Murtagh and Saphira stage a rescue, and Eragon escapes with the unconscious elf. During the escape, Eragon and Murtagh battle with Durza. Murtagh shoots Durza between the eyes with an arrow, and the Shade disappears in a cloud of mist. Having escaped, they run off. Eragon succeeds in communicating with the elf, whose name is revealed as Arya, and learns the location of the Varden. After some arguing, Murtagh decides to still travel with Eragon to the Varden but is still wary of them.

An army of Kull (Urgals who can grow up to 8 feet) reach Eragon right outside the Varden's entrance, but are driven off with the help of the Varden, who escort Eragon, Saphira, Murtagh, and Arya to Farthen Dûr, the mountain hideout of the Varden. When they arrive in Farthen Dûr, Eragon is led to the leader of the Varden, Ajihad. Ajihad imprisons Murtagh after he refuses to allow his mind to be read to determine if he is a friend or a foe to the Varden. Eragon is told by Ajihad that Durza was not destroyed by Murtagh's arrow, because the only way to kill a Shade is with a stab through the heart. Orik, nephew of the dwarf King Hrothgar, is appointed as Eragon and Saphira's guide. Orik shows them a place to stay and introduces them to Hrothgar. Eragon also meets Ajihad's daughter, Nasuada, and Ajihad's right-hand man, Jörmundur. He also runs into Angela and Solembum, who have arrived in Tronjheim, and visits Murtagh in his prison. He is tested by two magicians, The Twins, as well as Arya.

Eragon and the Varden are then attacked by the Kull, as well as the rest of the Urgal army. Eragon personally battles Durza again, and succeeds in stabbing him in the heart with Zar'roc, but Durza slashes a deep cut like Murtagh's on his back. He then passes out, and is visited telepathically by a stranger while he is unconscious, who tells Eragon to visit him in the Elven capital, Ellesméra.

Eragon realizes that he needs to learn more and decides to take the advice of The Cripple Who Is Whole and go to the land of the elves in order to study magic and fighting. Stability among the Varden is threatened when the leader of the group is killed in a follow-up Urgal-tracking operation; Eragon's friend Murtagh and a pair of sorcerers named the Twins disappear in the same operation. The Varden choose their fallen leader's daughter, Nasuada, to lead them; Eragon and Saphira, as important public figures, are asked to endorse this choice, which they do. Before they leave the land of the dwarves, the dwarf king asks to adopt Eragon as an honorary member of his family. Nasuada decides to move the Varden to the free land of Surda to organize another strike against Galbatorix.

Meanwhile, Eragon's cousin, Roran, returns to their home village of Carvahall hoping to marry the butcher's daughter, Katrina. The village is besieged by imperial soldiers, led by Galbatorix's sinister agents, the Ra'zac, who are looking for Roran. The villagers begin resisting; they fight well, but their opponents are more powerful and vow to destroy the villagers. When the Ra'zac capture Katrina, Roran organizes his community to travel en masse to Surda to join the resistance, a journey that is completed only with many hardships, and which changes Roran into a toughened, sometimes ruthless leader.

Eragon, Saphira, Arya, and a dwarf named Orik travel to Ellesméra, the capital city of the elves, which is buried deep in a forest, for further training. There the elves reveal to him The Cripple Who Is Whole, an elderly Dragon Rider; he and his dragon can no longer fight, but they instruct Eragon and Saphira. Eragon becomes a very powerful magician and fighter and, in a ritual celebrating the origin of the Riders, a mysterious dragon magic alters his form so that he takes on the strength and appearance of an elf rather than a person. Meanwhile, he falls in love with Arya, who rebuffs his many advances; the match would be impossible, because she is over a hundred years old and an elf princess.

Finally, Eragon and Saphira realize through magical means that Galbatorix's army is massing for a major attack and go to join the Varden and the people of Surda in the battle. Roran and the villagers arrive via a stolen boat, and Roran makes an important contribution to the battle. Eragon fights mightily, but at a crucial moment another rider appears; one of the two eggs in Galbatorix's position hatched and Murtagh, who was captured from Farthen Dûr because of the treachery of the Twins, has become a Dragon Rider sworn to do Galbatorix's will. As he fights his former friend, Murtagh reveals to Eragon that they are brothers; Murtagh's father, a treacherous Rider who betrayed the order to follow Galbatorix, is also Eragon's unknown parent. Murtagh's magic is more powerful than Eragon's, but he lets Eragon escape. Eragon and Roran are reunited and decide to call each other brother and attempt to rescue Katrina and kill the Ra'zac.

Eragon, Saphira, and Roran travel to Helgrind, the home of the Ra'zac, the creatures that had killed Eragon's uncle, Garrow. Before entering Helgrind, Eragon and Roran observe a pagan service in worship of Helgrind. There they rescue Roran's betrothed, Katrina, who was being held prisoner, and kill one of the Ra'zac. Saphira, Roran, and Katrina return to the Varden, while Eragon stays behind to kill the remaining Ra'zac and dole out a suitable punishment to Sloan; Katrina's father who was imprisoned in Helgrind. (Eragon was reluctant to kill him). While he is fighting the remaining Ra'zac, it mentions that Galbatorix has discovered the name of all names. Eragon doesn't understand, and ignores the Ra'zac after it pleads for mercy, and kills it. After consulting the elven Queen Islanzadi, they come to an agreement on how to punish Sloan. Sloan is condemned to never meet his daughter again. Eragon arranges affairs so that Sloan will regain eyesight in the future, should he repent for his crimes. As Eragon travels back to the Varden, he confronts a hermit in the name of Tenga(He is later revealed to be a teacher of the herbalist, Angela). Arya the elf had come in order to protect Eragon, as he traveled through the Empire. They have a conflict with a group of Soldiers, meet some spirits as they travel to the Varden. Arya reveals about her association with Faolin and crafts a boat made of grass, whilst Eragon sings a flower for her. Once they return to the Varden, Eragon discovers that Katrina is pregnant with Roran's child and a wedding is arranged, which Eragon is to conduct. Just before it begins, a small force of enchanted troops attack alongside Murtagh and his dragon, Thorn. The enchanted soldiers had spells cast by Galbatorix on them that stripped them of the ability to feel pain. King Orrin, King of Surda, discovers a method to kill the soldiers; behead them. Elven spell-casters aid Eragon and Saphira and cause Murtagh and Thorn to flee back to the Empire, winning the battle. After the fight, Roran marries Katrina. The leader of the Varden, Nasuada, then orders Eragon to attend the election of the new dwarf king in the Beor Mountains. He leaves with much reluctance as Nasuada forced Saphira to remain in the Varden, in order to protect the Varden from Murtagh and Thorn. Eragon travels with Nar Garzhvog, Leader of the Urgals to Bergan Hold, ancestral home of the Durmigst Ingentium. They see a Shrrg, Nagra and an enormous bear, which Eragon regarded as a threat even for Saphira, on the way. After staying for a brief period in Bergan Hold, where he is shown the forest of stone, Eragon heads to Farthen Dur where the new dwarf king is to be elected. Once among the dwarves in Farthen Dur, Eragon is the target of a failed assassination, found to be the work of a dwarf clan, whom the dwarf Orik then forces into exile. Having earned the sympathies of the dwarves, Orik is elected the new king. Saphira arrives to Farthen Dur for Orik's coronation and reconstructs Isidar Mithrim, the star rose which was destroyed in the battle of Farthen Dur.

After Orik's coronation, Eragon and Saphira return to the elven capital Ellesméra to train. There, Saphira revealed from a memory that Eragon's deceased mentor, , is Eragon's father; which Brom asked her to show him when the time was right. Oromis and Glaedr too justify Saphira's revelation. Glaedr also reveals the source of Galbatorix's power: Eldunari, or heart of hearts. An Eldunarí allows the holder to communicate with or draw energy from the dragon it belongs to, even if the dragon is deceased, or a great distance away. Galbatorix spent years collecting Eldunari, and forcing the deceased dragons to channel their energy to him through their Eldunari. Saphira is delighted to learn of the existence of the dragons, although imprisoned by Galbatorix's dark magics. After training, Eragon visits , the elven blacksmith who forges swords for Riders. But Rhunön wouldn't create a weapon for him because long ago she swore an oath never to create a weapon again after the Fall of the Riders. Also her stocks of the metal, required to forge rider's swords was completely exhausted. But by deciphering the werecat Solembum's instructions Eragon is able to acquire the metal he requires from under the roots of the Menoa Tree. After Eragon's repeated requests, Rhunön creates a weapon by controlling Eragon's body. Eragon gives a name to the sword,"Brisingr." As Eragon's body itself forged the sword, a special bond between the sword and Eragon had been created, thus making the sword burst into flames whenever Eragon utters Brisingr, even when he does not intend to use magic. Oromis suspects that "Brisingr" is part of the sword's true name. Before Eragon and Saphira depart for the Varden, Oromis says that the time has come for him and Glaedr to openly oppose the Empire in combat alongside the Queen of the Elves, . Thus, Glaedr gives his own Eldunari to Eragon. If anything should happen to Glaedr, Eragon would still be able to get advice from him. Then Glaedr and Oromis fly to Gil'ead, while Eragon and Saphira fly to Feinster, the city that the Varden are laying siege to.

Meanwhile, Roran is sent on various missions as part of the military force of the Varden. One of the targets is a convoy of supply wagons guarded by enchanted soldiers that can't feel pain. The unit suffers extreme casualties, and the commander Martland Redbeard is replaced after losing his hand. During a mission to attack a large enemy force raiding a village, plans made by the new commander, Captain Edric almost cause the operation to fail, but Roran gives new orders and kills one hundred and ninety-three enemy soldiers by himself, leading the Varden to victory. Despite saving the mission, Roran is charged with insubordination and is as a punishment. After the public whipping, Nasuada promotes Roran to commander and sends his unit on a mission. He leaves in command of a group of both men and Urgals to enforce the idea of men and Urgals working together. When an Urgal, Yarbog, challenges Roran for leadership of the unit, he wrestles the Urgal and forces him to submit. After returning to the Varden, his squad joins the siege of Feinster, a city in the Empire. As the siege begins, Eragon rescues the elf and departs to find the leader of the city, but discovers that three magicians are attempting to create a Shade. While racing to kill the magicians, Eragon has a vision through Glaedr's Eldunarí showing Oromis and Murtagh fighting. Murtagh is using power of several Eldunari, and Glaedr and Thorn fight in the sky. Soon Glaedr is badly wounded. In the midst of the fighting, Galbatorix Murtagh and tries to lure Oromis to his side: when he fails, and after Oromis suffers a seizure, Galbatorix uses Murtagh to kill him. Glaedr, in grief, is then also killed. After the vision, the magicians have managed to create the Shade . Eragon and Arya fight desperately to slay Varaug. Eragon then distracts Varaug by battling him through the mind, which Arya takes advantage of by stabbing Varaug in the heart. After the successful siege, Nasuada tells Eragon the Varden's plans for invading the Empire. Arya and Eragon are now both known as Shadeslayers.

When the Varden attack Belatona, a city of the Empire. In the battle, Saphira, Eragon's dragon, is nearly killed by a Dauthdaert (death spear) called Niernen —a spear from the Dragon Wars intended to destroy magical wards and kill dragons. Belatona is soon captured by the Varden, and an alliance is later formed between the Varden and the werecats.

Afterwards, Eragon's cousin Roran is sent on a mission to capture Aroughs, which proves to be a difficult task. He comes up with a risky plan and Aroughs is taken, although Roran's men suffer many injuries. Roran rejoins the Varden at Dras-Leona when they are in the process of making plans to attack the city. Murtagh and his dragon Thorn are occupying the city, therefore not allowing a chance to attack the city directly. Jeod finds information on the entrance to a sewer system that was never completed under the city. Assuming the existence of a secret tunnel into the city, Eragon leads a small group (himself, Arya, Angela, the werecat Solembum, and an elf named Wyrden) into the city to open the gates for the Varden. It turns out that the tunnels are used by the priests of Helgrind, and Eragon and Arya are captured after being separated from Angela and Solembum and witnessing the death of Wyrden. Because the priests are angry at Eragon for killing their gods (which are revealed to be the Ra'zac themselves), they intend to feed Eragon and Arya to Ra'zac hatchlings. Eragon and Arya struggle and injure themselves while being held captive until Angela and Solembum save them. However, Eragon loses the Belt of Beloth the wise. Eragon is then able to open the city gates and defeat Murtagh and Thorn, allowing the Varden to take control of the city. In the middle of the night, while Eragon and Arya are drunk, Murtagh and Thorn attack the Varden's camp and capture Nasuada. In her absence, Eragon is appointed as the leader of the Varden as they march on to Urû'baen in hope of overtaking the city.

Eragon remembers Solembum's advice (from the first book Eragon) telling about the Vault of Souls and the Rock of Kuthian. He invites Solembum to his tent and questions Solembum's knowledge of the Rock of Kuthian, of which the werecat has none at all. During the conversation, Solembum loses himself as a new voice talks to Eragon before abruptly ending, bringing Solembum back from a trance he cannot remember. Eragon eventually discovers that the Vault is on Vroengard Island. Eragon then talks with Glaedr about the Vault of Souls but Glaedr is unable to remember the conversation. Eragon realises that very powerful magic is causing everyone in Alagaesia —except for Saphira and himself— to forget about the Vault of Souls and the Rock of Kuthian after they hear of it. After Eragon finds a way (by special words) to remind and let Glaedr understand him, Glaedr believes that Eragon is telling the truth and advises him and Saphira to immediately find the source of and reason for the powerful magic, as it could help them in the fight against Galbatorix. Eragon and Saphira take Glaedr's Eldunarí as a guide.

After a while on the island, Eragon and Saphira learn that they must speak their true names in order for the Rock of Kuthian to allow them to enter. After days, they find their true names and the rock opens. Inside, the three of them find a hoard of Eldunarí and dragon eggs that were hidden away before Galbatorix destroyed the Riders. Umaroth, the dragon of Vrael (the last leader of the Dragon Riders) who speaks for all of the Eldunarí, says that the time has come for them to reveal themselves and to help Eragon and the Varden to overthrow Galbatorix. Eragon and the others leave Vroengard with all the Eldunarí save five, who volunteer to stay and guard the eggs, and as they pass through the rock back onto the surface to open land, their knowledge of the existence of the stored dragon eggs is removed from their minds. They make their way to Urû'baen, where the combined forces of the Varden, the elves (led by Queen Islanzadí), the werecats (led by Grimmr Halfpaw), the Urgals (led by Nar Garzhvog) and the dwarves (led by King Orik) are preparing to attack Urû'baen.

Eragon and Saphira reach Urû'baen as the siege begins. The Eldunarí are revealed to the leaders of the Varden and all of them form a plan to attack the city. The forces of the Varden attack Urû'baen while Eragon, Saphira, Arya, Elva, and eleven elven spellcasters led by Blödhgarm break into Galbatorix's citadel. They cautiously make their way to the throne room after progressing through a series of traps, during which the elven spellcasters assigned to protect Eragon are taken captive. In the throne room, Galbatorix subdues Eragon, Saphira, Arya, and Elva and informs them that he has learned the true name of the ancient language, which he referred to as the Word. With the Word he is able to control the usage of magic with the ancient language. Galbatorix orders Murtagh and Eragon to fight using only their swords; Eragon eventually defeats Murtagh. Murtagh, whose oath to Galbatorix was broken due to a recent change in his true name, uses the Word to strip Galbatorix of his wards. Enraged, Galbatorix renders Murtagh unconscious and attacks Eragon with his mind, while Saphira and Thorn attack Shruikan. Using energy from the Eldunarí, Eragon casts an empathy spell to make Galbatorix understand his crimes, and experience every piece of pain and suffering that he has caused from the last 100 years. Meanwhile, Arya kills Shruikan using the Dauthdaert. When the pain and agony he has caused becomes unbearable, Galbatorix utters an incantation for unmaking himself, which results in an explosion that destroys most of the citadel. Eragon, using energy from the Eldunarí, is able to protect those in the citadel.

Murtagh and Thorn, being freed from their oaths of loyalty to Galbatorix, retreat to somewhere in the north to have some time to themselves to do some thinking and to heal from their ordeal. Before leaving, Murtagh teaches the Word to Eragon and then bids him farewell - the two Riders forgiving and acknowledging each other as brothers -. Nasuada, after a heated debate with the leaders of the Varden, becomes the High Queen of Human Alagaësia and King Orrin of Surda grudgingly pledges his allegiance to her. Arya returns to Du Weldenvarden to help choose a new queen for the elves after the death of Queen Islanzadí, her mother, in battle, and is chosen. She takes with her the rescued green dragon egg, which soon hatches for her. Thus, Arya becomes a Rider with her dragon named Fírnen.

Eragon reworks and rephrases the magic of the original pact between Riders and dragons to include both dwarves and Urgals, allowing the dragon eggs to hatch for members of their races. Eragon, coming to the decision that there is no safe place to raise the dragons and train new Riders in Alagaësia, begins planning to sail away with the Eldunarí and the eggs to a region far east of Alagaësia. He leaves two eggs in Alagaësia: one is to be sent to the dwarves, and the other to the Urgals. Those future Riders will travel to Eragon's new home for training, while new eggs will be sent back to Alagaësia to hatch for new Riders. 

(There isn't the ending here.  To know the original ending, you can search it online)