When Tikki tries to stop Plagg from eating a piece of cheese in the classroom, Ms. Mendeleiev, Collège Françoise-Dupont's physics teacher, catches them, but they escape. Ms. Mendeleiev tries to prove the existence of the magical creatures on a TV show, but the viewers are not convinced by her theory. Marinette and Adrien become convinced that their partner must be one of their fellow students, and Adrien even specifically suspects Marinette; conversation reveals that they must give up their Miraculouses if their identities are compromised, even to each other. Angry that no one believes her theories, Ms. Mendeleiev gets akumatized into "Kwamibuster", a Ghostbusters-themed villain with a vacuum to capture kwamis. Both superheroes lose their kwamis to Kwamibuster, so Adrien hides in a costume, and Marinette flees to Master Fu. She borrows many other Miraculouses despite the physical risk, and has Mullo of the Mouse Miraculous transform her into "Multimouse", giving her the power to divide herself into miniature clones. Some of her clones also use "unify" to undergo alternate transformations and employ the various kwamis to best Kwamibuster, freeing all the captured kwamis. Multimouse then uses the Fox Miraculous to make it appear that Marinette and Ladybug are two different people to erase any idea from Cat Noir of them being the same person. Cat Noir apologizes to Ladybug for his kwami being at "that elementary school" (to convince her that he is not a student there) and discourages Ms. Mendeleiev from making any more attempts to prove the kwamis are real. Marinette returns all of the extra Miraculouses to Master Fu. He remarks how exceptionally strong Marinette is to have used so many at once.

A villian from the future travels back in time to try to defeat Ladybug and Cat Noir when they are younger. The heros meet a hero from the future who had been trapped in the pass for centuries.

Mr. Ramier is akumatized into Mr. Pigeon for the 72nd time but this time he can turn people into evil pigeons.

Ladybug and Cat Noir face someone they know well - and of whom they never thought that one day they would have to fight against him.

After stealing the Miracle Box, Shadow Moth turns into Monarch and uses the Rabbit Miraculous to return to a vulnerable moment in Ladybug and Cat Noir's past to capture their Miraculous.

Marinette decides on giving up her love of Adrien to avoid any more disasters and focus on preparing to battle Monarch, but the days go by and no akumatized villains have appeared yet. Has Monarch given up?

What if Monarch could force the Kwamis who know Ladybug's address to lead him to her? The unfortunate little creatures would have no choice but to obey him... And if Monarch showed up at Marinette Dupain-Cheng's home, would she be able to escape him?

Marinette is surprised to discover that a former schoolmate, Socqueline, is posing as Ladybug. She tries to dissuade her from taking such a risk, but Monarch has his eyes on her.

While Marinette tries to convince herself that she has to stop being in love with Adrien because it diverts her from her superhero role, she discovers that she has feelings for someone else.

Marinette tries to convince herself that she loves Chat Noir to forget about Adrien. Adrien has given up on being in love with Ladybug, is trying to declare his feelings to Marinette.

Marinette uses Tikki's Reunion to summon Johanne of Arc, a previous Ladybug holder, to ask about the possible romance between her and Chat Noir. Meanwhile, Pharaoh is reakumatized and asks questions for Ladybug to solve.

Tikki and Plagg are sad to see their carriers so sad to be forced to give up their feelings. The Kwamis will then make a radical choice that will change many things in Paris.

Monarch is faced with a unique opportunity that he refuses to lose. The Kwamis made a decision that completely distracted Marinette and Adrien from their responsibilities. For better and for worse.

Marinette's friends decides to help her to get closer to Adrien, then the whole gang finds out that one should always be clear with friends.

Luka develops a special interest in Bob Roth, who would do anything to make money. Luka himself would do anything to defend his values and his friends.

Marinette starts to feel traumatized when she and Adrien prepare to have a normal date at the pool as she once had a crush on Kim last year and Chloe pulled a series of nasty pranks on her.

Monarch is ready to do anything when he senses a unique occasion to get a real second chance even if it is his last chance to seize the Miraculous.

As the gang comes up with yet another overcomplicated plan to bring Marinette and Adrien together, Lila uses her talent for manipulation to persuade Kagami that Marinette is a liar who abuses everyone else's kindness. Shocked, Kagami is akumatized into Riposte Prime. She lays into Marinette at the very moment when Adrien had managed to finally make her feel comfortable around him. Will Lila's poisonous lie ruin the friendship between Kagami, Marinette and Adrien?

When Marinette and Zoe are chosen to organize the end-of-school-year party, Marinette learns that Zoe is secretly in love with someone in ninth grade at school. Zoe says that she cannot talk about it. To Marinette, this can only mean one thing: Zoe is in love with Adrien! But before she finds out whether she is right or not, a common enemy of the girls will try to ruin their beautiful friendship

Adrien must attend a dance organized by his father and Mrs. Tsurugi. He will be the King of the Ball alongside Kagami, who has been chosen to be this year's Queen. But neither of them wish to go for the dance.

Marinette decides to have a heart-to-heart with the father of the boy she loves. By seeing her courage her friend Kagami finally dares talk to her mother.

Lila uses an incident in class to calls for new elections to replace Marinette as class representative.

Junior high will soon be over, Lila and Chloe are planning to defend their classmates' future before their teachers; Marinette and Adrien worries what the two brats' next evil plan will be.

The end of school year is nearing, and rebellion is brewing. Monarch decides to on a plan that is dangerous for his secret identity and for Ladybug and Cat Noir, too.

Chloe and Monarch are more powerful than ever, Ladybug and Cat Noir wonder about their powers. Marinette and Adrien's lives are about to change forever.

Adrien disobeys father to go find Marinette but she discovers a secret nothing could have prepared her for.

Monarch places the final pieces of his villainous plan on his chessboard of evil.

Monarch's ultimate plan is in motion. Nothing seems able to stop him now. Especially considering that, while the world descends into chaos, the supervillain has just trapped Ladybug in person...