The Gate of Ivrel is about an exiled warrior named Vanye and how he comes into the service of Morgaine, Closer of the World Gates. The Gates are portals through time and space, left by a long-dead alien race, the qhal. Morgaine's job is to close them so that the disaster that had annihilated the qhal doesn't happen again. There are a few qhal survivors, and they don't want the Gates closed because for them, the Gates offer immortality. There are many Gates on many worlds, and this is the story of the Gate on Vanye's world, The Gate of Ivrel.
 

The qhal, a humanoid species with white hair and pale skin, were an ancient and advanced civilization that controlled the Gates, passageways that allowed them to travel vast distances instantaneously through both Time and Space. The qhal destroyed their own empire when one qhal decided to travel backwards in time. This resulted in small anomalies in Time and Space that snowballed until Time rebounded and Reality wiped itself out. A few worlds survived, and bits of qhal culture survived on these worlds.

The Gates survived.

Over one hundred years ago, in Andur-Kursh, a war took place between the princes of Andur and the witch-lord Thiye of Hjemur-beyond-Ivrel. The princes were aided by five strangers, one of which was a white-haired woman, perhaps of qhal blood. Together with the five strangers, the princes and ten-thousand men gathered to meet Thiye.

They then discovered that the five strangers had deceived them. Thiye's men outnumbered them by more than ten to one. The princes were slaughtered. A single survivor awoke on the field to find nothing but a few corpses with no apparent wounds on them. Of the enemy, there was no sign. The five strangers had also disappeared. Only the white-haired woman returned, but she was chased by the people and fled to the hill of Stones. There, she vanished. The hill is supposedly cursed, and people make offerings to keep her from returning....

In the present world of Andur-Kursh, Nhi Vanye i Chya is of clan Nhi, a clan known for its obsessive Honor, independence, stubborness, and constant plottings and betrayals. Vanye's father is the lord of the Nhi. His mother was of clan Chya, a clan known for being volatile, artistic, and proud. His two elder brothers have a different mother, and they often beat the illegitimate Vanye remorselessly until one day, Vanye strikes back and accidentally wounds one brother and kills his eldest brother, Kandrys.

Vanye is banished in disgrace as an ilin, a warrior with no lord, forced to serve one year under any lord who is willing to take him. Vanye travels through the hill of Stones where of a sudden, a white haired woman appears on horseback from out of thin air between two pillars that mark the site known as Morgaine's Tomb. Morgaine kri Chya has returned after over 100 years trapped in the Gate.

Morgaine takes Vanye into her service and becomes his liyo, his liegelord. Vanye knows that Morgaine is dangerous and serving her will get him killed. However, he is honor-bound to obey her will. Morgaine reveals her mission to Vanye: Kill lord Thiye of Ivrel and destroy the gate.

Morgaine and Vanye are taken prisoner by Kasedre, the lord of Leth, who is insane. Kasedre is in awe of Morgaine and wishes her to tell him all about the past battle against Thiye at dinner. Morgaine agrees in exchange for information from one of Kasedre's old books. In the book, she comes across the name of a man she knew: Zri. she suspects that Zri, counselor to one of the Andur princes, was the actual betrayer of the princes instead of the five strangers. 

Kasedre reveals that Zri was tutor to many of his ancestors. Zri disappeared mysteriously one day. Kasedre then asks to see Morgaine's famous sword, Changeling, which was forged at Leth. Morgaine refuses to unsheath it, stating that it brings disaster whenever drawn. Kasedre throws a fit at being denied his request. He quiets down only when his tutor Chya Liell enters the room.

That night, Liell warns Morgaine and Vanye that Kasedre intends to kill them. Liell helps Morgaine and Vanye escape. He joins them. While fleeing, Liell secretly approaches Vanye and warns him that Morgaine is not to be trusted. Vanye's honor will not allow him to leave his liegelord, and he turns down Liell's pleas to leave Morgaine and join him instead. Liell suddenly attacks him. Vanye fights off Liell and, shaken, catches up with Morgaine. During their flight, Vanye and Morgaine see various strange otherworldly creatures in the woods at night. Morgaine tells him that these creatures were brought through the gate at Ivrel by Lord Thiye. 

Morgaine and Vanye encounter the forestmen of Clan Chya, ruled by Vanye's cousin, Chya Roh. Clan Chya fears Morgaine, and Vanye has never been welcome there, but Roh allows them to take shelter for one night. Roh assures them that Chya will fight off Liell and the Leth, who are still after them. Roh later tells Vanye that Liell, who was originally of Clan Chya, had been a good man until he went to Leth. He tells Vanye that there is something very strange about Liell, that he is old, old like Thiye is old. 

Roh also tells Vanye that if he manages to survive his year of service with Morgaine, he will be welcome in Chya. Although Roh's welcome offers Vanye hope for the first time since his exile, it is also unwittingly cruel, since Vanye and Roh both know: Vanye will not survive his service under his cold liyo who would not hesitate to sacrifice him to succed in her mission....