Frankenstein 1818), which can be considered the first real science-fiction novel, is subtitled “The Modern Prometheus.” Its author, Mary Wollstonecraft Godwin, was the mistress and later the wife of Percy Bysshe Shelley, the Romantic poet who wrote Prometheus Unbound (1820) and who was in part the model for Victor Frankenstein. In Frankenstein Unbound, Brian W. Aldiss combines the titles of Mary and Percy Bysshe Shelley’s books and sends a time traveler from the twenty-first century back to Geneva in 1816, when Mary was engaged in writing her as yet uncompleted novel.

Frankenstein Unbound begins in the summer of 2020, in a series of letters from Joseph Bodenland—a liberal presidential adviser ousted by right-wing extremists and now staying at his ranch in New Houston, Texas—to his wife in Indonesia. The world is at war, but Joe hopes that the news of a space-time rupture will stop further conflict. Meanwhile, he is enjoying the company of his grandchildren, who still believe in myths. Their mythic make-believe games cause him to think of the major myth of his own time: “that ever-increasing production and industrialization bring the greatest happiness for the greatest number all round the globe....”

The infrastructure of space has become unstable because of nuclear warfare above the stratosphere. Joe thinks that “the intellect has made our planet unsafe for intellect. We are suffering from the curse that was Baron Frankenstein’s in Mary Shelley’s novel: by seeking to control too much, we have lost control of ourselves.” In New Houston, Joe experiences a thirty-five-hour timeslip back to the Middle Ages. Then, Mrs. Bodenland receives a cable stating that during a second timeslip, her husband rode out alone into an altered countryside, and when the ranch snapped back into the present, he and his car disappeared into the vanished land.

From that point onward, the novel is the taped journal of Joe Bodenland, relating his experience. He discovers that he has slipped in time and place back to Switzerland in 1816, when people are discussing the just-ended Napoleonic Wars. His years as a diplomat had made him knowledgeable about the country and fluent in its languages. He also finds that he has become young again and full of vigor. At an inn, he overhears gossip about a local murder, in which a maidservant named Justine Moritz was to stand trial for killing a small boy, William. Joe is surprised when a gentleman whose table he is sharing insists that Justine is innocent and that guilt lies on his own shoulders. Following his distraught acquaintance to Geneva, Joe learns that the man is Victor Frankenstein. “I felt myself in the presence of myth and, by association, accepted myself as mythical!” Joe follows Victor into the mountains, where they both see the monster.

As a child, Joe had read Frankenstein, but the original was confused for him by “the deplorable pastiches and...