A Novel
by Kotaro IsakaA gripping novel mixing mythology, family drama, espionage, and high technology from the international bestselling author of Bullet Train, already in development for a major film starring Anne Hathaway and Salma Hayek.
In Seesaw Monster, international bestselling author Kotaro Isaka employs his hallmarks of kinetic pacing, high-stakes action, and great characters to explore the nature of conflict, the power of close relationships, and the idea of progress.
Poor Naoto. A pharmaceutical salesman in Japan in the booming 1980s, his job has him working long hours, answering to his demanding boss and entertaining entitled customers. And at home, his wife, Miyako, and his mother are always feuding, making each other miserable. Why can't the two just get along?
Then one day a mysterious visitor shows up at their door with a possible answer. Their conflict is larger—and far more ancient—than it might appear. When Naoto uncovers something wrong at work and his life is suddenly in danger, can the two women set aside their differences to save him?
Decades later, in our near-future, surveillance, facial-recognition software, and AI dominate Japan. The most sensitive information lives only on paper, and Mito makes his living delivering it. When a chance meeting with a stranger on a train draws Mito into a possible conspiracy, he finds himself face-to-face with his own enemy, a tragic double whose life has been intertwined with his own. Is this another instance of the ancient feud? And what role will Miyako, now in her nineties, play in this deadly game?
In this novel, structured as two interconnected novellas spanning decades, Isaka explores moral and social issues surrounding technology like AI and self-driving cars that are pressing in today's context. Interestingly enough, Isaka's book is actually visionary: Seesaw Monster first appeared in Japan in 2019, when these technologies were not yet so dominant. Now translated into English by Sam Malissa—who also brought Isaka's Bullet Train to international audiences—it is already set for a film adaptation starring Anne Hathaway and Salma Hayek. Both novellas are entertaining, page-turning stories that explore interesting ideas about the cyclical nature of conflict. Isaka blends a bunch of genres: espionage thriller, speculative fiction, and social commentary go hand in hand with propulsive storytelling. The "seesaw" becomes a central metaphor of a possible but fleeting balance. But Isaka chooses to end this enjoyable book on a hopeful note: if conflict is humanity's constant, so too are many other emotions—compassion, understanding, concern, fairness—that can restrain both technological dangers and our own destructive impulses...continued
Full Review
(675 words)
(Reviewed by Alicia Calvo Hernández).
The publication date of this review corresponds in the Japanese era calendar to Reiwa 7/09/10, or September 10, 2025.
Japan uses two dating systems: the Gregorian calendar, used in most Western societies and adopted in Japan in 1873, and the system of imperial eras (gengō 年号), which divides time according to the reign of each emperor. Each era begins with the ascension of a new sovereign to the throne and ends with his death.
When a new reign begins, the count resets to year one. Japan is currently in the Reiwa era, inaugurated in 2019; therefore, the year 2025 is Reiwa 7. This era followed Heisei (1989–2019), which followed Shōwa (1926–1989), the period in which the first novella of Seesaw Monster ...

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