在得知艾俊去上海后，马丽娜借着给舅公送生日礼物的机会也来到了上海。可刚到上海，马丽娜的手机、米可幻奇以及精灵宝奇都被偷走了！束手无策的她接受了一个名叫飞儿的女孩的帮助，殊不知就是飞儿偷走了她的东西。她们一起对抗贪财的钞票张，愤怒的他被黑魔蝶黑化了。原来黑魔蝶特意来上海抢夺魔法珠宝“普洛幻奇”。飞儿在普洛幻奇的加持下变身成为超级英雄“仁人”，可满脑子只为复仇的她违背了魔法超能力所要求的品质，导致普洛幻奇的守护者被黑化成为阎罗狮，就连黑魔蝶和黑猫罗尔都被他消灭了！只剩下失去搭档的奇迹少女和失意的仁人来对抗这个超强反派。她们能否解开彼此的心结？飞儿是否可以放下心中的仇恨成为称职的新英雄？

马丽娜是住在现代法国的巴黎少女，因为一次善举获得神秘老人的认可，得到了能变身为超级英雄奇迹少女的力量。同样获得变身能力的还有马丽娜的同班同学艾俊，他是知名设计师之子，因家庭过度保护长期在家自学，第一天上学却阴错阳差使马丽娜误会其恶作剧。双方在不知道对方真实身份的情况下，以奇迹少女及黑猫罗尔之名义拯救被黑化的巴黎市民，而艾俊对马丽娜澄清恶作剧一事后，艾俊温文的风度使得马丽娜开始想和他交朋友，一见艾俊便手足无措，但是艾俊却崇拜上智勇双全的奇迹少女，以黑猫黑尔的身份几度示爱，都被心有所属的马丽娜拒绝。两人面临的挑战除了爱情问题，还有在巴黎制造混乱的邪恶反派。

By daylight, Marinette Dupain-Cheng and Adrien Agreste are ordinary teenagers. But unbeknownst to their family and friends, the two of them carry a huge secret...using the powers of magical creatures called Kwami, they transform into the superheroes Ladybug and Cat Noir! With a mission to protect the city of Paris from the evil Hawk Moth, the two of them must learn to cope with their new responsibilities, as well as ordinary troubles involving love, school, family, and friends. Most of all, they must learn to put their romantic feelings aside in order to perform their duty, unaware of each other's true identities.