High school student Seo Jiwoo possesses a secret and terrifying power: super speed. Fearing his own abilities, he lives quietly, using his gifts only to secretly rescue stray cats and help those in need. His life is upended when he discovers a bedraggled stray cat in an alley. To his shock, the orange tabby speaks, revealing itself to be Kayden Break, one of the most powerful and notorious Awakeners in the world. Gravely injured after being ambushed by three of the world's top-ranking Awakeners, Kayden was forced to transfer his consciousness into a feline form to hide and recover.

Set primarily in modern-day Seoul, the story follows the unlikely partnership between a kind-hearted boy who has never found his place and a short-tempered, battle-obsessed recluse. As Kayden recuperates in Jiwoo's home, he takes on the role of a reluctant mentor, teaching Jiwoo how to control his speed and even granting him a secondary electrical ability, leading to the series title Eleceed, a portmanteau of electricity and speed. Their fateful encounter drags Jiwoo into a hidden world of Awakeners, individuals with superhuman abilities who operate within a complex society of associations, academies, and dangerous conspiracies.

The central characters include the main protagonist, Seo Jiwoo, a compassionate high schooler who evolves from a fearful boy into a formidable Awakener under Kayden's tutelage. Kayden Break, the deuteragonist, is a cantankerous and overwhelmingly powerful cat who seeks to fight the world's top 10 rankers. Key allies include Yoo Jiyoung, the young and influential chairwoman of the Shinhwa Association and Korea's strongest Awakener, who wields wind abilities and becomes Jiwoo's sponsor; Kartein, a top-50 global healer who also ends up living with Jiwoo in cat form; and Pluton, another powerhouse with immense durability who transforms into a dog. Rivals and antagonists emerge from organizations like Frame, a multinational syndicate of rogue Awakeners.

The narrative unfolds through several notable arcs. The early Awakener World Arc establishes the foundation, introducing Jiwoo's training, his first real enemies like the Klein Brothers, and his entry into the Korean Awakened Academy where he meets crucial friends such as Jisuk Yoo and Subin Lee. The Academy Exchange Arc expands the scope globally, pitting Jiwoo against international students and introducing the concept of the World Awakened Academy. Subsequent arcs, including the Invasion Arc and Rescue Arc, raise the stakes as Jiwoo and his friends confront powerful families and the sinister Frame organization. Major conflicts arise during the Hunt Arc, which features a climactic confrontation where Kayden battles the world's top 10 rankers, and later arcs continue to explore the hierarchy of elite Awakeners and ongoing threats like the powerful being Astra. Throughout these challenges, Jiwoo grows stronger, learning different Force Control techniques from his various mentors, while his bond with his surrogate feline family deepens.