Plot

Ordinary teenager Marinette's life in Paris goes superhuman when she becomes Ladybug. Bestowed with magical powers of creation, Ladybug must unite with her opposite, Cat Noir, to save Paris as a new villain unleashes chaos unto the city.

This exciting Miraculous origin story follows shy Parisian teenager Marinette (Cristina Vee Valenzuela) as she starts the year in a new high school. On her way home, Marinette saves a mystical old man who gives her the Miraculous gem, transforming her into the superhero Ladybug, bestowed with powers of creation. At school, Marinette has fallen for Adrien (Bryce Papenbrook), the sheltered son of millionaire fashion designer Gabriel Agreste (Keith Silverstein). Meanwhile, Adrien has been transformed by another Miraculous gem into the superhero Cat Noir - and begins to fall for Ladybug, his opposite. Unaware of each other's true identities, the duo team up to battle the supervillain Hawk Moth, who in reality is none other than Adrien's father, seeking control of the Miraculous gems to bring his wife back to life. With Hawk Moth sowing chaos and destruction across Paris, Ladybug and Cat Noir's talents are put to the test in fierce battles with his minions. Yet still greater tests lie ahead. Can Marinette, as Ladybug, find the courage to believe in herself? Will this star-crossed hero and sidekick become something more to each other when their masks come off?—Netflix

Marinette Dupain-Cheng, a socially anxious teenager, goes to school trying to avoid being noticed. Despite sparking a friendship with another student, Alya Césaire, Marinette finds herself desperately attempting to avoid the wrath of rich girl Chloé Bourgeois. While attempting to escape, Marinette runs into Adrien Agreste and develops a crush on him. Adrien has become incredibly emotionally distant from others due to his mother Emilie's passing. Similarly wracked by her death, Adrien's father, Gabriel, uses the Butterfly Miraculous, a magical jewel, to turn into Hawk Moth, to find the Miraculous he needs to make a wish and bring his wife back to life.

Hawk Moth's appearance is sensed by Wang Fu, guardian of the Miracle Box, who chooses to release the Ladybug and Cat Miraculous, only for them to run away. He is saved from an incoming bus by Marinette, still running away from Chloé, while he realizes that she deserves the Miraculous. Marinette ducks into a corner shop in an alley and is found by Tikki, the Kwami of Creation, while her polar opposite, Plagg, the Kwami of Destruction, makes his way to Adrien.

Both become Ladybug and Cat Noir and eventually run into each other, working together to defeat the Gargoyle, an "akumatized" villain created by Hawk Moth from negative emotions. Following the fight, Wang Fu follows them and stresses the importance of them sticking together.

Marinette initially refuses to continue being Ladybug, but Hawk Moth recruits more villains and they wreak havoc at a carnival. Gathering the courage to fight, Marinette transforms once again, and defeats them, alongside Cat Noir.

Months pass, and Marinette plans to confess her feelings to Adrien, whilst Adrien plans to confess to Ladybug. Being unaware of their true identities, neither confession goes well. Defeated, Hawk Moth akumatizes himself and unleashes an apocalypse on Paris, prompting Ladybug and Cat Noir to go into action. The heroes are overwhelmed, and Ladybug has her earrings taken, but Marinette can briefly power through to help push Cat Noir away from Hawk Moth. When Cat Noir's mask is damaged, Hawk Moth discovers that Adrien is Cat Noir, he renounces his Miraculous powers and breaks down. Adrien forgives his father, while Marinette reclaims her earrings and returns the Butterfly Miraculous to Wang Fu before repairing the damage done to Paris with her powers. Gabriel is possibly arrested, while Marinette returns to her family.

The day of the Winter Ball arrives, and Marinette arrives in a beautiful dress much to the crowd's pleasure. She finds Adrien, revealing that she knows his identity, having seen his reconciliation during the fight, and reveals her identity as well. They then share a kiss.

Later, Nathalie Sancoeur, the Agrestes' assistant, goes to the basement underneath their house. In the basement is the body of Adrien's mother, wearing the Peacock Miraculous.