劇情設置在現代巴黎，中法混血的Marinette Dupain-Cheng（瑪麗內特·杜平-程）是壹個普通的中學女生，性格有些猶疑羞澀，夢想成為時裝設計師，暗戀同班的帥氣男生Adrien Agreste（阿德裏安·阿格裏斯特）。當有壞人威脅巴黎時，Marinette化身正義勇敢的英雄Ladybug（瓢蟲），搭檔愛調戲人的Chat Noir（黑貓），壹起打擊邪惡勢力。但Marinette並不知道面具下的Chat Noir正是她壹直不敢表白的男生Adrien，而Adrien也不知道自己的暗戀對象Ladybug卻是Marinette。

　　Set in modern-day Paris, the series focuses on a teenage junior high school girl named Marinette Dupain-Cheng and her classmate and crush Adrien Agreste. When evil arises, Marinette becomes a superhero named Ladybug, while Adrien becomes Chat Noir/Cat Noir. Not knowing each other's true identity, the two work together to protect Paris from a villain named Hawk Moth who covets their powers.