Published in 2009, "Beautiful Creatures" by Kami Garcia and Margaret Stohl is the first installment in the Caster Chronicles series. The novel, written in a remarkably short 12 weeks, was initially conceived from a bet between the authors and seven children. It centers on Ethan Wate, a sixteen-year-old in the fictional town of Gatlin, South Carolina, who finds himself drawn to Lena Duchannes, a mysterious newcomer with magical abilities. Despite being a Mortal, Ethan possesses a unique connection to Lena, allowing him to protect her from darker forces. The narrative explores themes of destiny, as Lena faces a critical choice on her sixteenth birthday to be claimed by either Light or Dark magic, a decision that carries immense consequences for her family and the magical world.

The story delves into the complex history of the Duchannes family and the ancient "Book of Moons," which has cursed their lineage, removing their free will in choosing their magical alignment. Ethan and Lena uncover this history through visions of their ancestors, Genevieve Duchannes and Ethan Carter Wate, whose tragic story is tied to the curse. Their forbidden romance is fraught with danger, as Lena's mother, Sarafine, a powerful Dark Caster, attempts to sway Lena to the Dark side. The plot culminates in a dramatic confrontation on Lena's birthday, where her choice and Ethan's fate are tested, leading to unforeseen magical consequences and a significant sacrifice.

The novel introduces a hidden world of "Casters," individuals possessing magical powers, who live alongside Mortals. Lena Duchannes belongs to this lineage, and her family grapples with a hereditary curse originating from an ancient spell in the "Book of Moons." This tome, used by Genevieve Duchannes in an attempt to resurrect her deceased fiancé, Ethan Carter Wate, irrevocably altered the family's destiny. The curse dictates that each Caster will be claimed by either Light or Dark magic on their sixteenth birthday, stripping them of personal choice. This predetermined fate creates significant internal conflict, particularly for Lena, who fears embracing the Dark side. The lore also includes entities like "Incubi" such as Macon Ravenwood, who subsists on dreams, and his brother Hunting, who feeds on blood, adding layers to the supernatural elements.

At its core, "Beautiful Creatures" explores the tension between predetermined destiny and individual free will. Lena's impending "Claiming" is a central conflict, representing the struggle against an inescapable fate imposed by the "Book of Moons" curse. Her relationship with Ethan Wate, a Mortal, challenges the boundaries between their worlds. Their telepathic connection, known as "Kelting," highlights a profound bond that transcends physical limitations and the inherent dangers of their inter-species relationship. The narrative questions whether love and personal choice can overcome ancient curses and societal prejudices, as Lena and Ethan fight against the forces that seek to dictate their lives and futures.

The story features a diverse cast of supernatural characters beyond the core Caster lineage. Amarie "Amma" Treadeau, Ethan's grandmother figure, is a "Seer" with the ability to commune with the deceased, known as "the Greats." Macon Ravenwood, Lena's uncle, is an "Incubus" who refrains from feeding on blood, opting for dreams instead. His brother, Hunting Phineas Ravenwood, embodies the darker, blood-feeding aspect of their kind. The narrative also revisits the tragic tale of Genevieve Duchannes and Ethan Carter Wate, whose ancestor-level story directly influences the present-day plot, demonstrating how past actions and curses echo through generations, impacting the lives of their descendants.