Seesaw Monster by Kotaro Isaka is divided into two sections with very different themes, yet they’re deeply connected in ways that only become clear as the story unfolds.
In the first part, Naoto Kitayama’s mother lives alone after her husband’s death. Worried about her, Naoto moves in with his wife, Miyako Shiota. From their first meeting, Miyako and her mother-in-law, Setsu, clash endlessly. What begins as a domestic drama soon turns dark when Miyako, a former secret agent, starts suspecting her father-in-law’s death wasn’t natural and that her husband might be framed in a work-related fraud.
The second part, Spin Monster, shifts to a futuristic Japan driven by advanced technology. A tragic accident leaves one boy as the sole survivor of two families, raised by grandparents Naomasa Mito and Kagetora Hiyama, who share no bond despite their shared loss.
Fast forward, when an AI creator is murdered after sending a mysterious message through Mito, he becomes entangled in a dangerous conspiracy that could spark a war. Hiyama, now a police detective on the case, crosses paths with Mito once again. To my surprise, Miyako, now known as Miyako Setsu, a celebrated children’s book author in her nineties reappears, tying the two worlds together in an unexpected way.
Here, AI doesn’t just think, it feels, possessing an uncanny intuition that can predict and possibly manipulate future outcomes, posing real danger to humanity. Compared to the first part, this section is far more complex and layered, filled with unreliable characters and shifting truths. A mix of family drama, mystery, and sci-fi thriller, Seesaw Monster is both emotionally charged and intellectually gripping, an inventive exploration of human connection, suspicion, and the cost of progress.