The Crystal Cave

Mary StewartFiction | Novel | Adult | Published in 1970

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Plot Summary

The first book of Mary Stewart's four-volume Arthurian Saga is set in fifth-century Britain, a land fractured by tribal conflict and Saxon invasion after the withdrawal of the Roman legions. The story is narrated by an aged Merlin looking back on his life, from his childhood as a royal bastard to the night he engineers the conception of the future King Arthur.

Merlin, called Myrddin Emrys as a child, grows up in the palace at Maridunum (modern Carmarthen) in South Wales, the illegitimate son of Princess Niniane. His mother has never revealed his father's identity despite beatings from her own father, the King, and rumors hold that Merlin was fathered by a demon. Scorned by his grandfather, Merlin is taken up briefly by his uncle Camlach, the new heir, who turns hostile after Merlin instinctively refuses a poisoned apricot, revealing an uncanny perceptiveness. Camlach views even this powerless child as a dynastic threat and wants him confined to the priesthood.

Merlin finds refuge in two secret places: the palace's disused Roman hypocaust, a network of underfloor heating tunnels where he eavesdrops on private conversations, and a cave in the hills that he discovers at seven while following a merlin, a type of falcon. Behind a gap in the cave's rock wall lies a small chamber entirely lined with crystals. The cave belongs to Galapas, an elderly scholar who has foreseen Merlin's arrival through his own prophetic gift, called the Sight. Over the following years, Galapas becomes Merlin's true teacher, instructing him in medicine, herbalism, astronomy, and eventually the art of making fire, described as the first and most fundamental form of magic.

At twelve, Merlin enters the crystal cave alone. Firelight reflected through the crystals triggers his first prophetic vision: a flooded mine inside a hill. Galapas urges him to join his grandfather's journey to meet the High King Vortigern in North Wales. On the return south, near a crag called Dinas Brenin, Merlin discovers the entrance to the very mine from his vision. A later vision reveals that his grandfather has died and Camlach has seized the throne. Cerdic, the Saxon groom who has been Merlin's only friend, has been killed for his role in the King's accidental death. Merlin sets fire to Cerdic's room as a funeral pyre, escapes over the palace wall, and is seized by Marric and Hanno, Breton spies working for Aurelius Ambrosius, the exiled claimant to the British throne who commands an army in Less Britain (Brittany).

In Brittany, Merlin escapes the ship and stumbles into the path of Ambrosius. He describes a vision of a man killing a white bull beside a standing stone, which corresponds to a secret ceremony of Mithras, an ancient mystery religion Ambrosius has revived to unite his officer corps. Ambrosius, intrigued, takes Merlin into his household. During a long night of questioning, the truth of Merlin's parentage emerges: Years earlier, wounded on a secret mission to Britain, Ambrosius was nursed in Galapas's cave by Niniane. They became lovers, but she refused to follow him, and he never knew she bore a child. Ambrosius acknowledges Merlin privately but explains that as a bastard, Merlin can never be a legitimate heir. Instead, Ambrosius envisions him as a prophet and counselor whose Sight will serve the kingdom.

Merlin spends five years in Brittany studying under Belasius, a brilliant tutor who secretly leads an outlawed druidic sect, and learning engineering from Tremorinus, Ambrosius's master builder. He absorbs songs from a blind Breton singer that encode ancient methods for raising great standing stones. Cadal, his assigned servant and bodyguard, becomes a steadfast companion.

When news arrives that Vortigern's hold on Britain is crumbling, Ambrosius sends Merlin ahead as a scout. Merlin finds Galapas dead and his cave ransacked. In Maridunum, his cousin Dinias, now destitute in the half-ruined palace, drunkenly calls Merlin fatherless in a tavern. Vortigern's agents overhear: This is the exact qualification the King's soothsayers have prescribed, as they need the blood of a fatherless boy to consecrate the cracking foundations of Vortigern's fortress at Dinas Brenin. Merlin and his mother are seized and brought north.

Before Vortigern's court, Niniane tells a careful fiction about being visited by a spirit in the dark, protecting Ambrosius's identity. The priests accept the tale and demand Merlin's execution. Merlin saves himself by leading Vortigern into the mine beneath Dinas Brenin. Torchlight reflecting off the flooded pool triggers a prophetic seizure in which Merlin speaks of red and white dragons and foretells Ambrosius's victory. He collapses and wakes honored as the King's prophet. When the drained pool yields no literal dragons, Merlin seizes two simultaneous omens, Vortigern's white-dragon banner falling into mud and a shooting star blazing overhead, to command Vortigern to flee. He escapes with Cadal. Three days later, Ambrosius lands at Totnes with his army.

Ambrosius burns Vortigern out of his fortress, defeats the Saxon leader Hengist at the battle of Kaerconan, and is crowned King of all Britain. During the campaign, Merlin works as a doctor among the wounded and knows through the Sight that his mother died at sunset on the day of battle. After two years with the army, Merlin withdraws to his cave at Bryn Myrddin, telling Ambrosius that the god does not speak to those who have no time to listen.

Ambrosius commissions Merlin to build a permanent monument at Amesbury, both a memorial and a burial place. First, Merlin accompanies Uther, Ambrosius's younger brother, on an expedition to destroy the fortress of Killare in Ireland, where Merlin identifies and transports a massive king-stone from a sacred circle. News meets them at Caerleon that Ambrosius has fallen gravely ill, reportedly poisoned. Merlin then raises the stones of the Giants' Dance (Stonehenge), using wooden-crib engines and techniques encoded in the blind singer's songs. He aligns the great stone arch so that at the winter solstice, sunrise strikes through it onto the king-stone at the circle's center. Ambrosius is buried there, and Uther Pendragon is crowned King.

Uther almost immediately becomes consumed by desire for Ygraine, wife of his chief ally Gorlois, Duke of Cornwall. Merlin interviews Ygraine and finds her equally drawn to Uther but unwilling to act dishonorably. Sensing that this union is fated and seeing the shadow of a child not yet born, Merlin devises a plan: Ygraine will persuade Gorlois to take her to Tintagel, the impregnable island fortress on the Cornish coast, while Gorlois moves to a separate stronghold. Merlin disguises Uther as Gorlois and leads him through a storm-lashed night to a hidden postern gate. They pass the guards, and Uther enters Ygraine's chamber.

That same night, Gorlois attacks Uther's camp from his own position and is killed. His captain Brithael rides to Tintagel with the news. Cadal intercepts Brithael on the cliff path and is mortally wounded; Merlin fights Brithael and kills him. Merlin finds Cadal dying and promises that the child conceived this night will be the sum of all their lives. Cadal asks Merlin to make the sign for him and dies.

Uther, arriving afterward, condemns Merlin for the bloodshed and refuses to acknowledge the child, dismissing Merlin back to Wales. Merlin accepts without argument. He gives Cadal's body to the sea and rides alone into the valley as the storm clears. Above, the great herald star still burns, and as it fades, the young sun rises over the land.