When Félix, Adrien's cousin, visits Paris and sows discord between Adrien and his friends, Alya, Rose and Juleka get akumatized into the Trio of Punishers. Can Ladybug and Cat Noir stop the three villains and reason with Félix?

Marc, Nathaniel, Alya, Zoe, Rose, Juleka, Mylene, and Alix try to help Marinette get closer to Adrien, but Chloe has filmed the incident on video and she plans on showing the video to Gabriel at his gala. Marinette disguises herself as a waiter so she can erase the video from Chloe's phone and prevent Adrien from getting homeschooled. Chloe is forced to relinquish her phone, but she secretly grabs her SIM card. Gabriel confronts Felix for taking his wedding ring from him and he gives his uncle a fake ring. Shadow Moth creates a sentimonster of himself. "Gabriel" threatens to get rid of Felix for his thievery, making him vulnerable to akumatization, but he is able to resist Shadow Moth's influence and Felix makes his escape. Shadow Moth akumatizes his sentimonster instead. Chloe steals Bob Roth's phone so she can show her video to "Gabriel". However, Chloe and Bob get captured by "The Collector" on his tablet and he soon begins to imprison everyone else on his tablet. Ladybug and Cat Noir manage to get Felix to safety. The two heroes are able to defeat "The Collector", Ladybug unknowingly gives "Gabriel" a magical charm. Chloe tries to show her video to "Gabriel" again, but Bob Roth gets his phone back and he erases the video, leaving Chloe humiliated and dismayed that her plan has failed. However, Felix begins to realize that his uncle is a supervillain. Marinette goes home and her friends come up with a comic book idea based on her adventures as a waiter. In a post-credit scene, Gabriel puts two fake miraculouses in his safe in order to lure his nephew into a trap.

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?

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.