The Atlantis Complex by Eoin Colfer

In this thrilling installment of the series, the genius anti-hero finds himself grappling with a psychological disorder known as the Atlantis Complex, which manifests as obsessive-compulsive behavior, paranoia, and multiple personality disorder. As he struggles with his mental health, a new threat emerges, endangering both the fairy and human worlds. With the help of his loyal allies, including a resourceful elf and a steadfast bodyguard, he must navigate his fractured mind and confront the looming danger to save the day, all while battling his inner demons.

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