Catalyst (Heroes' Day - Part 1)

"" is an episode of Season 2 of Miraculous: Tales of Ladybug & Cat Noir, and it is the first part of "Heroes' Day". It's world premiere was on October 21, 2018, in Switzerland for French viewers on RTS Deux.

Synopsis
Coming soon!

Plot
While they come to face a super-villain, Marinette and Adrien fall asleep when their ringtones sound. It's Heroes' Day and every Parisian has to do a good deed. Adrien caught his father in front of a stone statue of Emilie Agreste. Nathalie goes to talk to Gabriel and tells him that it is really time to implement his plan. Arrived at the school, our two protagonists face Lila Rossi who speaks to them by FaceCam. She tells them that she is in the country of Prince Ali and that she has received permission from other countries to make the Earth healthier. When actually, she still lives in Paris, near the school. She makes her mother, who surprises her, believe that she was talking to her "boyfriend" Adrien Agreste. We learn later that Lila's parents believe that the school closed because of the many akumatizations. Adrien and Marinette hear their comrades tell their good deeds, but Marinette could not take care of hers. Following a remark from Chloé, she tells her friends that she will do a tasting with lots of macaroons and other confectionery. Once back home, Marinette tells everything to her father and he tells her that it is impossible to achieve such a feat. Gabriel makes Lila have negative emotions by saying on television that Volpina is only a vulgar copy of superhero Ladybug. He re-akumatizes her and created an illusion of Akumatized Ladybug and Cat Noir fighting on top of the inflatable ballons of heroes floating in the air. The akumatized version of Ladybug kills Cat Noir in front of everyone by forcing him to use Cataclysm on himself. Hawk Moth removes the powers from Lila and tells her that he will find her again soon. Hawk Moth akumatizes Nathalie into Catalyst, and the latter allows Hawk Moth to akumatize several people at the same time. Hawk Moth then becomes the Scarlet Hawk Moth and transforms a big majority of the old villains.

Ladybug goes to fetch Master Fu, but Vanisher follows her. Ladybug purifies her and fetches the Bee Miraculous, Fox Miraculous and Turtle Miraculous. She entrusts the Fox Miraculous and the Turtle Miraculous to Alya and Nino in front of one another, which results in them discovering their respective identities. Cat Noir entrusts the Bee Miraculous to Chloé.

Scarlet Hawk Moth then appears in front heroes on the Eiffel Tower. The heroes are all together. The episode ends with a map of the Catalyst logo in close-up.

Major characters

 * Marinette Dupain-Cheng/Ladybug
 * Adrien Agreste/Cat Noir
 * Alya Césaire/Rena Rouge
 * Nino Lahiffe/Carapace
 * Chloé Bourgeois/Queen Bee
 * Gabriel Agreste/Hawk Moth
 * Tikki
 * Plagg
 * Akuma
 * Nathalie Sancoeur/Catalyst

Minor characters

 * Tom Dupain
 * Sabine Cheng
 * Emilie Agreste (statue and pictured)
 * Adrien's bodyguard/Gorizilla
 * Lila Rossi/Volpina
 * Caline Bustier
 * Ivan Bruel/Stoneheart
 * Nathaniel Kurtzberg
 * Sabrina Raincomprix/Vanisher
 * Mylène Haprèle/Horrificator
 * Alix Kubdel/Timebreaker
 * Lê Chiến Kim/Dark Cupid
 * Max Kanté/Gamer
 * Rose Lavillant/Princess Fragrance
 * Juleka Couffaine
 * Ali (pictured)
 * Lila's mother
 * Nooroo
 * Mr. Damocles
 * André Bourgeois
 * Nadja Chamack/Prime Queen
 * Dark Ladybug (illusion)
 * August's mother (background)
 * Nora Césaire
 * Ella and Etta Césaire
 * Jagged Stone/Guitar Villain
 * Clara Nightingale/Frightningale
 * Fred Haprèle/The Mime
 * Wang Fu
 * Trixx
 * Wayzz
 * Pollen
 * Fang (dragon form)
 * Gigantitan
 * Glaciator
 * Animan (Tyrannosaurus form)
 * Rogercop
 * Civilians
 * Students

Trivia

 * Rena Rouge, Carapace and Queen Bee return in this episode to assist Ladybug and Cat Noir in their mission.
 * This also marks the instance where all superheroes appear at once.
 * Alya and Nino discover each other's superhero identities.
 * Akumatized villains from Season 1 and Season 2 returns in this episode but instead of their usual designs, they are themed red-colored.
 * Those that have been reakumatized are: Volpina (however it is unknown if she was akumatized once more after Hawk Moth recalled her akuma), Prime Queen, Guitar Villain, Frightningale, Horrificator, Stoneheart, Gamer, Princess Fragrance, Gorizilla, Dark Cupid, The Mime, Timebreaker, Vanisher, Animan, Rogercop, Gigantitan, and Glaciator.
 * This episode has shown the most transformation sequences, having a total of six transformations, surpassing "Sapotis" and "Anansi", which only had three and "Queen Wasp", which only had four.
 * A new version of Alya's transformation sequence is shown when she transforms in her everyday attire.
 * Also Rena Rouge's eyelids are now black whenever she blinks as opposed to "Sapotis" where her eyelids remain uncolored.
 * The Lucky Charm and Miraculous Ladybug are not used in this episode.
 * This the second time Ladybug didn't call on her Lucky Charm.
 * This episode shows Hawk Moth removing someone's powers for the first time.
 * This episode shows an Akuma self de-evilization without Ladybug purifying it for the first time.
 * During Nino's transformation, Carapace's theme has a new theme compared to his transformation during "Anansi."

Errors

 * Alya's bangs are miscolored throughout the episode.
 * During the illusion of akumatized Ladybug, her earrings aren't inverted.
 * Marinette doesn't have her earrings at one point when she's in the kitchen.
 * When Volpina gets deakumatized by Hawk Moth, the tips of her hair are brown instead of white.
 * Ladybug gives Cat Noir just the Bee Miraculous by itself, but when he gives it to Chloé, it's in the box.
 * Though Lila's mother is shown to be Clara Contard, it was said by Thomas Astruc to be an animation error.

Catalyst (Der Heldentag - Teil 1) Catalizadora pt-br:Catalisadora (O Dia dos Heróis - Parte 1)