Lady Gertrude Groan, the mistress of Gormenghast, gives birth to Titus, the Lord of Gormenghast’s heir and successor. The very same day, the kitchen apprentice Steerpike, who has been constantly humiliated and harassed by the kitchen-chef Swelter, manages to flee from the kitchen located deep in the cellar vaults of the castle.
Steerpike’s escape route involves a daring ascent up the castle’s facade, until he finally reaches its expansive roof. With Gormenghast at his feet, Steerpike experiences a new and euphoric freedom.
Exhausted he falls into a deep sleep, but is eventually woken by Fuchsia, daughter of the Lord. Steerpike cunningly gains Fuchsia’s sympathy and loyalty, thus making sure she will not betray him. Fuchsia introduces him to Lady Cora and Lady Clarice, the twin sisters of Earl Groan. Their childlike dreams of power make them the perfect pawns for Steerpike’s monstrous schemes of ambition. He becomes their servant and counsellor.
Steerpike is now able to observe life at the court of Gormenghast in great detail: the mysterious Lady Gertrude who only loves her pets and constantly talks to them, the gloomy Lord of the castle, who is devoted only to his books and their son Titus who it mute. Gradually Steerpike succeeds in winning Fuchsia’s love.
Seven years pass. One day, during a family ritual, the gigantic library goes up in flames. Steerpike, who had secretly set fire to it, manages to appear as the saviour. Steerpike, now enjoying the esteem of the court, becomes the apprentice and helper of the fanatic, malicious Master of Rituals, Barquentine, a crippled old dwarf.
Steerpike seals the lips of the twin sisters, whom he had used for his awful crime, spins them into a cocoon, in which they slowly die. Meanwhile, the Lord of Gormenghast, despairing over the loss of his beloved books, falls into depression and madness. He transforms into an owl. Only Titus has grasped Steerpike’s real ambitions, but he is a child, and he is mute.
Finally, Steerpike gets rid of Barquentine and thus becomes Master of Rituals himself. He now gains total control of the castle. But Fuchsia has lost all belief in him. In her despair she throws herself out of a window.
Titus runs away from life at court, for he knows that he is the only one standing in the way of the megalomaniac Steerpike. He manages to survive in the castle kitchen, which has been abando-ned since Steerpike’s seizure of power.
Here, where Steerpike’s hateful career had its beginning, Titus has a significant encounter which changes his life completely and gives him the strength to combat Steerpike.
In Lady Gormenghast’s chamber we encounter Steerpike in obscene rapture. He slaughters all her pets and humiliates the Countess.
Titus puts an end to the nightmare. He kills Steerpike and leaves Gormenghast.