In a room at Le Grand Paris, Jagged Stone is playing a new piece on his on electric guitar before being greeted by his agent Penny Rolling and his manager Bob Roth. Jagged Stone asks for Bob's opinion, to which he replies that it's not bad. However, in order to increase Jagged Stone's popularity, Bob suggests recording a duet with the new number one star, XY. Jagged Stone immediately refuses, resulting in an argument with his manager. Jagged Stone says that Penny agrees his music is the best, while Bob retorts that he requires that Jagged Stone be on top of the sales. Jagged Stone then angrily shoves back Bob's suggestion of an album cover design, proclaiming it's not "him." Bob tells him this look is the one that is gaining popularity and insists he uses it. Jagged Stone argues back, and, remembering the sunglasses he is wearing were made by a high school student, requests that Bob asks her to design the album cover.
Bob enters Tom & Sabine Boulangerie Patisserie and requests that Marinettecreates the album cover. He hands her XY's album to show her the style he wants. Marinette comments how the style is not Jagged Stone's style, but Bob insists she uses it as it is popular. Marinette eventually accepts the offer and her parents proudly hug her. In her room, Marinette is sketching the album cover while listening to XY's music, which she clearly dislikes. After a while, Marinette turns off the music in distress and complains about her distaste for XY's music, questioning why Jagged Stone would change his style and lamenting on her design. Tikki asks why Marinette designed it like that in the first place, to which she says she did as she was told. Tikki tells her to follow her instincts, but Marinette declines, saying she has to stick to Mr. Roth's expectations before complaining about the pressure. Tikki answers that Marinette should be able to handle pressure.
Later, Marinette is before Jagged Stone, Penny, and Bob in Jagged Stone's room with her proposed cover. Disappointed, Jagged Stone tells her that he doesn't like it and it isn't his style. Marinette agrees before admitting it was Mr. Roth's request, but Jagged Stone requests she remakes the cover in his style. After some encouragement, she agrees and heads off to redo the album cover.
After the others are gone, Jagged Stone is watching an interview with XY on TVi. The new pop star acts arrogant and foolish, claiming all music is related to technology to program what people expect, angering Jagged Stone. To make matters worse, XY completely aggravates Jagged Stone by describing him to Nadja Chamack as old, out of date and worthless. Furious, Jagged Stone throws his tablet into Fang's mouth and starts aggressively playing his guitar.
Hawk Moth senses Jagged Stone's frustration and sends an akuma after him and it possesses his guitar. Hawk Moth offers Jagged the chance to be the greatest artist of all time and seek revenge on XY, and akumatizes him into Guitar Villain, also akumatizing Fang into a dragon.
As Marinette thinks of an idea for the album cover, she meets Adrien outside. Before she can say Adrien's name correctly, Chloé shoves her aside and tells him that she organized a meeting with Jagged Stone for him. As they walk inside the hotel, Marinette realized that Adrien is a fan of Jagged Stone and decides to make the cover, this time with her own style.
Inside the lobby, Chloé and Adrien encounter Guitar Villain and his dragon. Guitar Villain shoots purple energy waves from his guitar and causes two nearby people in the lobby to dance uncontrollably. Once the elevator doors behind Adrien and Chloé open, Adrien sets her inside. Once the doors close, Adrien then transforms himself into Cat Noir so he can stop Guitar Villain.
After Guitar Villain makes several citizens—in addition to several pigeons and cars—dance uncontrollably, Cat Noir arrives. Guitar Villain starts to fight him, using his orange energy wave which he calls "Shocking Riff". Marinette has seen the commotion, and she quickly transforms herself into Ladybug. She arrives just in time to save Cat Noir from being burned into ash by Dragon Fang.
Dragon Fang flies away with Guitar Villain to the Eiffel Tower to start his revenge on XY. Once Guitar Villain gets to the Eiffel Tower, he punches what he believes to be XY, only to realize that he is actually a hologram. Guitar Villain then angrily asks Théo Barbot where the real XY is. After he first refuses to answer, Guitar Villain destroys the set around him with his "Awesome Solo" and Théo immediately tells him that XY is at the TVi studio. After Ladybug and Cat Noir follow and save Théo from dancing uncontrollably, Guitar Villain commands Dragon Fang to go to the studio.
However, Ladybug immediately phones Nadja Chamack and warns her and everyone else in the studio that XY is in danger. By the time Guitar Villain gets into the studio and the recording room, XY has escaped outside with Alec. But when Cat Noir and Ladybug try to get him to safety, Guitar Villain and Dragon Fang swoop in and take XY to the Eiffel Tower. They follow them to the Eiffel Tower as night falls.
At XY's concert, Guitar Villain has tied-up XY and is about to make him walk the plank on top of the Eiffel Tower. While Ladybug and Cat Noir are climbing up the Tower, he plays his guitar and green energy waves which he calls "Ultimate Solo" start to cause tremendous earthquakes around him. Once Guitar Villain stops playing, Ladybug uses her yo-yo as a grappling hook so she can pull herself and Cat Noir up faster. But Dragon Fang appears and pulls the string away, sends purple energy waves after them. Assuming that the akuma is inside the guitar and that it's too hard to get, Ladybug flies Dragon Fang into the top platform, and she and Cat Noir start climbing the Eiffel Tower again. At the same time, XY is about to fall because the plank under him is about to break.
Ladybug uses Lucky Charm, and a can of extreme hold hairspray appears. Using her lucky vision, Ladybug asks Cat Noir to distract Guitar Villain while she climbs above them. Cat Noir is about to use his Cataclysm as a shield against Guitar Villain's "Shocking Riff", but fails. Luckily, Ladybug uses the hairspray to stiffen Guitar Villain's hair in front of his face, preventing him from being able to play his guitar. But before she destroys the guitar, Ladybug quickly saves XY from falling with her yo-yo. This ends up making him land on the guitar and break it, revealing the akuma. Ladybug catches the akuma and purifies it. She then tosses the hairspray and cleanses the city, returning everything, including Jagged Stone and Fang, back to normal.
The next day, Marinette finally finishes the album cover for Jagged Stone. The latter is so impressed that he decides to use her drawing for his next album, much to Marinette's delight. Later, Nadja Chamack announces that Jagged Stone's new album became the number 1 of sales, overthrowing XY on the ranking.
At Collège Françoise Dupont, Adrien asks Marinette if she would sign an autograph for him. After she does, Chloé watches Adrien leave and starts chewing on a magazine of Jagged Stone out of jealousy. Marinette now declares to Alya that it's the best day of her entire life.
Characters
Major characters
Marinette Dupain Cheng/Ladybug
Adrien Agreste/Cat Noir
Hawk Moth
Akuma
Tikki
Plagg (transformation sequence only)
Jagged Stone/Guitar Villain
Fang
XY
Minor characters
Bob Roth[4]
Penny Rolling[4]
Nadja Chamack
Adrien's bodyguard
Chloé Bourgeois
Sabrina Raincomprix
Tom Dupain
Sabine Cheng
Alec Cataldi
Xavier Ramier (background)
August's mother (background)
Théo Barbot
Alya Césaire
Unnamed doorman
Jean Duparc (background)
Mireille Caquet (background)
Unnamed maid (background)
Aurore Beauréal (pictured)
Civilians