The novel begins with a Prologue in which Merlin introduces himself as an old man remembering all the events of his life. He presents his greatest memory in the prologue as well which details the love affair in the cave between his parents who we will learn later are Ambrosius and Niniane.
The Dove tells the story of Merlin's early years. We learn how is despise in his grandfather's house because his father is unknown and he is a bastard unrecognized. He begins to become aware of his power of the Sight and how to use it to his own advantage.
We are introduced to his uncle, Camlach, who tries to poison Merlin, because he fears his power. He discovers the crystal cave and meets Galapas, another person his life besides his mother who has the gift of the Sight. Galapas teaches him many aspects of life as well as how to use magic. He takes him into the crystal cave where Merlin has a vision of a deep mine underground where slaves are breaking out rock and taking them to the surface. He will later know that this mine lies under Dinas Brenin and will be the reason why the fortress being built there won't stand. Galapas later insists that Merlin ride along with his grandfather when he meets up with Vortigern, the High King, at Segontium. Here, Merlin first sees the hill that will become Dinas Brenin or the King's Fort. This place will be the one where Merlin nearly gives his life for a blood superstition.
This section of the novel also introduces the tension in the country, because the sons of Vortigern have broken with him and war is imminent. Quarrels break out between Camlach and Merlin's grandfather over whose side to take. Then, Merlin's grandfather is killed in a fall and Merlin's beloved servant, Cerdic, is blamed and killed as well. Merlin sees all this in a vision at the crystal cave. Merlin returns to his home long enough to pack supplies and burn down his room where Cerdi's body lies. This will be his way of sending his friend on his way in the manner he would have wanted.
After Merlin runs away, he is kidnapped by Marric and Hanno, two spies
of Ambrosius, who take him across the Narrow Sea (the English Channel)
to Less Britain.
The Falcon tells the story of Merlin's life in Less Britain. He arrives there, sea-sick and afraid that the two spies will kill him. He escapes from the boat and makes his way up a road toward the nearest town. This is when he first sees standing stones and the image of a two-headed axe which disappears before his eyes. This image will appear to him many times in the future and is a sign given by the god.
Merlin finds shelter in a cow shed where he has a vision of a man lassoing a great white bull and killing it. This is the sacred picture of the god Mithras who is worshipped by Ambrosius and Uther. When he awakes, Ambrosius and Uther are standing over him and demand that he relate the vision again. They take Merlin with them to Ambrosius' camp where the story of Ambrosius' and Uther's life in Less Britain is revealed. They had been taken in by King Budec when Vortigern had poisoned their brother, Constantius, the king, and stolen the throne. Now, they are amassing an army to take back their birthright and unify Britain.
Ambrosius speaks to Merlin about many things in Britain and later gives him a brooch for his cloak which carries Ambrosius' personal insignia, the Red Dragon. At this point, Ambrosius knows that Merlin is his son, but Merlin does not. Ambrosius also assigns Cadal as Merlin's personal servant.
Merlin is given a tutor named Belasius. One night, Merlin follows him and discovers he is the Arch Druid of a sect which believes in human sacrifice. Belasius tells Merlin that he wants him to be one the new initiates in this religion, but Merlin only acts like this is what he wants. On his way back to Ambrosius' camp, he is stopped by Uther who finds Belasius' bloody robe in Merlin's saddlebag and believes he is one of the members of this illegal sect. However, when he grabs Merlin by his cloak, he sees the Red Dragon brooch and stops short of hurting him. Merlin tells Cadal everything that happened to him while following Belasius and Cadal warns him to steer clear of both Belasius and Uther.
When he goes to tell Ambrosius what happened, he has vision in which
he sees Ambrosius with his mother Niniane going into the cave. He realizes
then that Ambrosius is his father and Ambrosius tells him the whole story
about how he met Niniane and how they fell in love. She had refused to
live in Less Britain with him, because she was too loyal to her father.
However, neither one ever stopped loving the other.
The Wolf relates some of the next five years Merlin spends in Less Britain. Camlach and Vortimer and his brothers bide their time by controlling most of West Britain even though their father is the High King. The Saxons continue to enjoy the benefits of raping Britain, because Vortigern doesn't have the troops to expel them.
Merlin spends those five years learning from his father, Belasius, and Tremorinus, the chief engineer of Ambrosius' army, as he waits to be of service to his father. When Merlin turns eighteen, Ambrosius is finally prepared to invade Britain. Merlin is sent on the first boat with orders to find Galapas who they hope will have information about Vortigern's army. Unfortunately, when Merlin finds the cave again, it has been trashed and burglarized and Galapas has been murdered. His next step is to find his mother, as she may know as much as Galapas. Before he can do that, however, he meets up with Dinias, his cousin and his childhood bully. They go together to an inn to eat and drink where Merlin hopes to learn as much as he can from him. While they are there, Merlin notices they are being watched by two mysterious Welshmen. Dinias tells Merlin that Vortigern is building a stronghold on the same hill where he saw Vortigern with his grandfather all those years ago. He plies Dinias with more wine to get him to talk, but it backfires on him when Dinias raises his voice too high, telling everyone there that Merlin is a bastard who never knew his father. This is of interest to the two mysterious men who take Merlin outside and force him and his mother to ride with them to Vortigern's court.
At Vortigern's court at Dinas Brenin, Merlin's mother tells Vortigern that Merlin's father was a demon, hoping to keep them from knowing that his real father is Ambrosius. Unfortunately, it is exactly what Vortigern wants to hear. He has been trying to build a stronghold at Dinas Brenin and the walls have cracked and fallen four times. Now one of his magicians tells him that they will only stand if the blood of a bastard who does not know his father is placed in the foundation. Merlin is that bastard. Merlin now must use his wits to survive. He takes the king into the mine cave and shows him a rock shaped like a dragon, hoping the light from the torches will create a magic effect around the rock. Instead, he falls into another vision during which he tells the king he must drain the pool by means of a conduit. Then, he prophesies through pictures of banners, wolves eyes, and the tail of a comet the defeat of Vortigern by Ambrosius. He also mentions the coming of artos or Arthur which those around him take to mean a bear. When the pool is emptied, there is nothing there to help Merlin's prophecy seem true. But a gust of wind grabs the king's banner and it falls into the pool of water left in the cave. The sunset leaves a reflection of red on the banner and the soldiers see it as a prediction that the banner will fall. At the same time, the comet from his vision flashes across the sky and Merlin screams that it is the voice of the god. He convinces Vortigern to strike his tents and leave Wales. This will help Ambrosius smoke him out later.
Merlin then gets away with Cadal and meets up with one of the officers
who stood around him when he had his vision. The man is not really an
officer of Vortigern, but is instead Gorlois, the Duke of Cornwall. He
has come to spy for Ambrosius, too, and is now able to hook up with Merlin.
They ride to meet Ambrosius and three days later, he comes ashore.
The Red Dragon relates how Ambrosius takes Britain. It takes him more than two years to pacify this country. Using Caesar-speed (to move fast and live off the land), he meets up with his allies in Britain. He unifies all these tribes and assimilates them into his army. Then, he finds Vortigern at Doward and because the fortress there is impregnable, he burns them out and kills them.
In flashback, we learn that Merlin, Cadal, and Gorlois rode on to meet Ambrosius with plans to ambush Vortigern's troops who had take Merlin's mother home. Along the way, they meet up with men from the countryside who are eager to be a part of Ambrosius' army. Once they have killed those troops of Vortigern's, they give the weapons and horses to the countrymen who want to volunteer. Merlin sees Dinias in Maridunum and convinces him to ride south and persuade pockets of men there to join him and Ambrosius.
Merlin also discovers that his mother is ill, but believed to be recovering. He goes to her and tells her everything that has happened to him since he left his grandfather's house, including the truth about Ambrosius. She is content to know he has been happy and Merlin, in his heart, knows she is dying. The only message she sends with Merlin to his father is: When I see him again, it will be time enough. Unfortunately, she dies before she can see the love of her life again. When Merlin leaves the convent, he sees a young nun to whom he is attracted. But in his heart, like the knowledge of his mother's death, he knows love is not meant for him.
Ambrosius' army defeats Hengist and the Saxons at the Battle of Kaerconan. Merlin watches it all on a hill above the plain where they meet. Later, Ambrosius executes Hengist, but gives him an honorable funeral. The army then travels to York where Ambrosius begins his great task of reconstruction in every city he visits. He also accepts the Christian God as his own and leaves behind the worship of Mithras. He believes he must live as his people do and they are Christians for the most part.
Merlin visits the Giant's Dance near Amesbury and has a vision about
a stone missing from an indentation in the ground within the circle of
the stones. It reminds of a grave and he knows the god has led him there
for a reason. Later, he sees Keri, the young nun, coming to his cave where
she attempts to seduce him. Merlin wants the love she offers, but the
god won't allow it and Merlin repudiates her. Later, he is sent to Ireland
to use his magic to somehow break the heart of the Irish. King Gilloman
has allied himself to Pascentius and threatens Ambrosius. Ambrosius believes
Merlin can end the battle before it even begins. He goes there and spends
the night lying in the middle of the Dance of Killare, the Irish standing
stones. He realizes that the black stone lying in the middle is the one
which exactly fits the indentation in the midst of the Giant's Dance.
He tells Uther that this rock is the heart of Ireland and if they take
it back, it will protect Britain forever. Using his own calculations,
Merlin figures out how to lift the stone and take it home with him. An
Irishman tells him that it had been prophesied that Merlin would appear
one day and take the rock, which had been brought to Ireland originally
from Britain. Therefore, it is only justice that it return. Merlin feels
bound by the god to bring back the stone, because he knows that his father
is ill and this stone will become his monument. When he arrives home,
Ambrosius has already died. Merlin has him buried within the circle of
the Giant's Dance and he raises all the stones around his grave and places
the black stone on top. Uther then becomes king.
The Coming of the Bear opens with Uther's reign beginning in a troublesome way when Hengist's brothers and the Saxons rise up again to challenge him. Fortunately, with Gorlois' help, Uther defeats them and solidifies his power. On December 20, the winter solstice, Merlin shows Uther the ultimate monument he has made for his father: the stones of the Giant's Dance are all raised and at sunrise that day, the light breaks upon Ambrosius' grave, fulfilling his promise that he would deck his grave with light. Uther warns Merlin that he cannot be as close to him as he been to Ambrosius, but Merlin predicts that their stars will cross again.
At Easter, Merlin is commanded to attend Uther's coronation. When he
arrives, he discovers that Uther needs him, because he has fallen in love
with Ygraine the wife of Gorlois, the Duke of Cornwall. He wants Merlin
to bring them together. Merlin knows from the god that this is destiny
and that the child created between them will be the greatest king ever.
So, at the cost of the deaths of four men, Merlin fulfills Uther's desire
and Arthur is conceived. In the end, Uther blames the outcome on Merlin
and forgets it was his desire that prompted it all. Also, Gorlois is killed
when his troops attack Uther's and in the end, Uther rides to Tintagel
to claim Ygraine for his own. Merlin rides off, knowing that his destiny
still awaits him somewhere after Arthur's birth.