The Magi is a profound mediumistic novel dictated by the spirit Count J.W. Rochester and psychographed by the Russian medium Vera Kryzhanovskaia. Blending historical drama, occult philosophy, and astral adventure, the story follows Dr. Ralph Morgan, who has been transformed into the immortal Prince Supramati after consuming the elixir of long life.

Seeking to master the terrifying powers of his new existence, Supramati and his immortal wife, Nara, retreat to an isolated, storm-battered medieval castle in Scotland. Guided by the enigmatic immortal Dakhir, Supramati begins a rigorous initiation into the occult sciences. He studies the "primordial matter" that sustains the universe and descends into the realms of black magic to understand the destructive forces of evil.

Through mystical rituals, Supramati summons powerful demons and projects his astral body into the fourth dimension. There, he witnesses the tragic fates of Earth's suffering spirits and explores a dead, petrified planet that serves as a prison for vampiric entities known as larvae. When Supramati finally completes his training, he is shocked to discover that forty years have passed in the blink of an eye. Returning to a decadent, gold-obsessed society in 1940, he finds his old world unrecognizable.

The consequences of eternal life become chillingly clear when the ghost of his predecessor, Narayana, steals the primordial essence to resurrect a woman murdered centuries ago, plunging her into the despair of an unfamiliar era. Burdened by his immense powers and the harsh realities of immortality, Supramati travels to the Himalayas to study white magic under the great sage Ebramar, dedicating his infinite life to the pursuit of divine light.