Kotaro Isaka, the internationally acclaimed author behind Bullet Train and the subsequent Three Assassins series, returns with Seesaw Monster, a genre-defying novel that weaves together family dysfunction, ancient mythology, and technological dystopia into something uniquely captivating. Like a master magician revealing his tricks while simultaneously performing new ones, Isaka presents a dual-timeline narrative that explores whether we are doomed to repeat the conflicts of our ancestors, even as the world transforms around us.
The novel’s structure mirrors its central metaphor: a seesaw that tips between two distinct eras, each reflecting the other’s weight. In 1980s Japan, we follow Naoto Kitayama, a pharmaceutical salesman caught in the crossfire between his wife Miyako and his mother—two women whose mutual antipathy threatens to tear apart his sanity. Decades later, in a surveillance-heavy near-future, courier Naomasa Mito finds himself entangled in a conspiracy involving artificial intelligence, while being pursued by police detective Kagetora Hiyama, a man who triggers an inexplicable and visceral revulsion in him.
The Mythology That Binds
What elevates Seesaw Monster beyond conventional family drama and techno-thriller territory is Isaka’s introduction of an ancient mythology: the eternal conflict between the People of the Sea and the People of the Mountain. This isn’t merely window dressing but the novel’s philosophical core. Those descended from the sea (marked by blue eyes) and those from the mountains (distinguished by large, pointed ears) are fated to clash across generations, their animosity as natural and inevitable as opposing magnetic poles.
The brilliance of this mythological framework lies in how Isaka uses it to examine the nature of inherited conflict. Is the tension between Naoto’s wife and mother simply personality clash, or something deeper and more primal? When Mito and Hiyama encounter each other as adults, their immediate mutual revulsion speaks to wounds that predate their personal histories. The mythology provides both characters and readers with a way to understand conflicts that seem to exist beyond rational explanation.
Isaka’s Signature Style: Chaos with Purpose
Longtime readers of Isaka will recognize his hallmarks throughout Seesaw Monster: the rapid-fire pacing, the darkly comic situations arising from mundane circumstances, and the intricate plotting that makes seemingly random events coalesce into inevitable conclusions. However, this novel demonstrates a maturation in his approach to character development and thematic depth.
The author’s prose, expertly rendered by translator Sam Malissa, maintains the kinetic energy that made Bullet Train such a phenomenon while allowing for moments of genuine emotional resonance. Naoto’s exhaustion as he navigates between two warring women feels palpably real, while Mito’s car-related trauma is handled with surprising sensitivity for an author known more for his plot mechanics than psychological realism.
Technology as Double-Edged Progress
The near-future timeline serves as more than just a sci-fi overlay; it’s Isaka’s meditation on progress and surveillance culture. In Mito’s world, facial recognition technology is omnipresent, digital communications are constantly monitored, and the most sensitive information exists only on paper—hence the need for human couriers. The artificial intelligence Velkasery, created by researcher Terao Terashima and his colleague Atsushi Chusonji, represents both technological advancement and the potential for manipulation on a massive scale.
This technological framework allows Isaka to explore how ancient patterns of conflict adapt to new environments. The sea versus mountain struggle doesn’t disappear in the digital age; it simply finds new expressions through algorithmic manipulation and surveillance networks. The question becomes whether technology amplifies our worst impulses or merely provides new tools for age-old conflicts.
Character Development: Beyond Archetypes
While Isaka’s earlier works sometimes sacrificed character depth for plot complexity, Seesaw Monster strikes a more balanced approach. Naoto’s predicament as a man caught between two immovable forces resonates with anyone who has navigated family dynamics, while his genuine love for both women makes his situation tragically relatable rather than merely comic.
Mito emerges as perhaps Isaka’s most psychologically complex protagonist. His car-related trauma, stemming from a childhood accident, affects every aspect of his adult life, from his career choice to his inability to form close relationships. When faced with false memories and manipulated recollections, Mito’s struggle with identity becomes the novel’s emotional center.
The revelation that Miyako, Naoto’s wife, was once a spy adds layers to what initially appears to be a simple domestic drama. Her transition from active agent to picture book author (collaborating with her former enemy, Naoto’s mother) suggests that even the most intractable conflicts can find unexpected resolutions.
Structural Brilliance and Minor Faults
The dual-timeline structure serves the novel’s themes perfectly, with each era illuminating the other. The connection between past and future characters—particularly the family relationships spanning decades—creates a sense of inevitability that supports the mythological framework. Isaka manages this complex structure with remarkable skill, avoiding the confusion that often plagues multi-timeline narratives.
However, the novel occasionally stumbles under the weight of its ambitions. Some of the technological explanations feel perfunctory, more concerned with moving the plot forward than exploring their implications. The artificial intelligence subplot, while thematically relevant, sometimes feels disconnected from the more grounded family dynamics that form the novel’s emotional core.
Additionally, certain revelations about character relationships strain credibility. The coincidences required to connect all the various plot threads occasionally feel forced, as if Isaka is too eager to tie every loose end into a neat package.
Themes That Resonate
Beyond its entertaining surface, Seesaw Monster grapples with profound questions about human nature and social progress. The notion that conflict is necessary for evolution—that “without change, there can be no progress” and “forcing change requires some agitation”—runs throughout the novel. This idea manifests both in the personal relationships between characters and the larger societal tensions they navigate.
The novel also explores the reliability of memory and the construction of identity. Mito’s discovery that his recollections may have been manipulated forces him to question everything he believes about himself. This theme resonates in our current era of information manipulation and raises questions about how we know what we know about ourselves and our world.
Translation and Accessibility
Sam Malissa’s translation deserves particular praise for maintaining the novel’s distinctive voice while making it accessible to English-speaking readers. The cultural specificity of 1980s Japan pharmaceutical culture and future surveillance society both come through clearly without feeling over-explained. Malissa successfully preserves Isaka’s trademark blend of philosophical depth and page-turning momentum.
Comparison to Isaka’s Previous Works
Seesaw Monster represents both a continuation and evolution of Isaka’s literary project. Like Bullet Train and Three Assassins, it features multiple interconnected storylines, morally ambiguous characters, and situations that spiral beyond anyone’s control. However, this novel demonstrates greater interest in generational themes and family dynamics than his previous action-oriented works.
The mythological elements recall the urban legends and folk wisdom that appear throughout Isaka’s oeuvre, but here they’re more integral to the plot structure rather than mere atmospheric details. The result feels both familiar to series fans and accessible to newcomers.
Similar Literary Explorations
Readers who appreciate Seesaw Monster will likely enjoy other works that blend genre elements with family drama and philosophical inquiry:
- Hard-Boiled Wonderland and the End of the World by Haruki Murakami – Another dual-narrative Japanese novel mixing technology and mythology
- The Thousand Autumns of Jacob de Zoet by David Mitchell – Generational conflicts across different time periods
- Station Eleven by Emily St. John Mandel – Technology, human nature, and the connections between past and future
- The Left Hand of Darkness by Ursula K. Le Guin – Exploration of fundamental human conflicts through speculative fiction
- Never Let Me Go by Kazuo Ishiguro – Memory, identity, and the weight of predetermined fate
Final Verdict
Seesaw Monster succeeds as both an entertaining genre hybrid and a thoughtful exploration of conflict, progress, and human nature. While it may not achieve the pure kinetic thrills of Bullet Train, it offers something perhaps more valuable: a mature meditation on the patterns that shape our lives across generations.
Isaka has crafted a novel that works on multiple levels—as family drama, science fiction thriller, and philosophical inquiry. The mythological framework provides a compelling lens through which to examine both personal relationships and broader social dynamics. Despite occasional structural weaknesses, the novel’s emotional resonance and thematic depth make it a worthy addition to Isaka’s growing international reputation.
For readers seeking fiction that combines page-turning excitement with genuine intellectual substance, Seesaw Monster delivers on both fronts. It confirms Isaka’s position as one of contemporary Japan’s most versatile and thought-provoking authors, capable of finding universal truths within the most specific cultural contexts.
- Rating: A compelling blend of family drama and speculative fiction that showcases Isaka’s evolving literary sophistication while maintaining his signature entertainment value.