In this universe, Marinette becomes Hawk Moth's spy. She once had the earrings, but then she gave them up.
You can guess the rest.
"I was able to convince Ladybug and her team to give a small demonstration later this afternoon, right here, in Collège Françoise Dupont."
The moment Lila made her announcement, Marinette quickly texted Gabriel the news. Sure enough, he responded, telling her to keep a close eye on the spotted hero in order for their master-plan to finally be put to motion.
When afternoon came, true to Lila's words, Team Miraculous appeared in the middle of the school ground.
And all it took was a few compliments on the other team to anger a jealous spotted bug into making an insulting remark to every citizen in Paris.
Marinette has never seen so much heartbreak in a day. She did her best to comfort her classmates, but they were too hurt by Ladybug's words to even listen.
Then the butterflies arrived.
Instead of their usual black and purple colors, these butterflies were black and red. And they appeared in swarms.
They infected everyone who was filled with negative emotions, mostly past akumatized victims. This brought the return of many villains; Stoneheart, Horrificator, Timebreaker, Dark Cupid, Mime, Guitar Villain, Gamer, etc.
The only ones who weren't akumatized were the ones who kept positive and brave throughout the entire ordeal.
The doors to the school were slammed open by a giant red fist and grabbed Marinette. She struggled to break free from Gorizilla's hold as he brings her to who-knows-where.
Just as planned, Chat Noir saved her and brought her to the nearest safe place.
AKA; Agreste Mansion.
He sets her down in front of the double-sided doors before leaping away to detransform. Once he was gone, Marinette opened the doors and immediately went straight to Gabriel Agreste's office. She pressed the hidden buttons on the portrait and was brought down to Hawk Moth's secret lair.
She expected to find Hawk Moth standing in the center of the room, but instead, finds another one of his akumatized villains.
"Nathalie?" Marinette called.
The villain turned around to face the bluenette, "You will refer to me as 'Catalyst'."
Catalyst projected a hologram from her helmet, revealing Hawk Moth addressing his army of scarlet akumatized villains.
"He wants to express his gratitude towards your efforts." Catalyst remarked.
Marinette dipped her head down in guilt, "I wish it didn't have to be like this."
Catalyst seams emphatic to her feelings, "So do I."
Marinette accidentally stumbled into Gabriel's secret during Simon Says' attack. She was initially shocked, but decided not to tell Adrien, as it would break his heart if he knew his father was a villain mastermind.
A few conflicting feelings later, along with a flashback of Gabriel's tragic past, Marinette decided to aid him in his plans...and maybe help him realize this was all a huge mistake.
She almost succeeded after Style Queen.
But then... Chloe found a miraculous...
She wasn't the only one; Nathalie was also aware that her boss' unhealthy obsession was causing a strain between him and his son.
Together, the two women would sometimes secretly... conspire behind Gabriel's back just to get him to bond with Adrien.
The two watched the battle unfold; Team Miraculous was clearly getting the upper-hand. But thanks to Dark Cupid, one-by-one, the team were akumatized until Chat Noir was the last one standing.
Marinette felt guilty when she saw the hero retreat into the sewers due to being out-numbered. It's times like these she wished she didn't give up the earrings.
Helping a heartbroken father take-over Paris... wasn't helping either.
Suddenly, the cat hero appeared at the Eiffel Tower and engaged Hawk Moth in an one-on-one battle, which led him to destroy the butterfly villain's cane.
Since Catalyst cried in frustration upon seeing the weapon destroyed, this means that every villain Hawk Moth created have reverted back into their civilian forms.
But in the heroes' case...
Marinette knew Hawk Moth never had a full confrontation with the heroes before, especially with 5 of them in the same place.
She quickly dashed out of the lair, and back into Gabriel's office. She opened the safe behind the portrait, (Don't ask how she knows the combination) and grabbed the jewelry in front of Mrs. Agreste's photo.
"Duusu, up high!"
It shouldn't have ended like this! He should've won! Victory should've been his!
As he braced himself for the heroes' attack, Hawk Moth failed to notice the dark blue feather flying into his broken cane. He shot his head up in surprise, a glowing blue outline appearing on his face.
"Hawk Moth..."
That voice... No... She didn't
"I am Mayura." The voice continued to echoed in his head, "You're surrounded. Let me help you."
"No." Hawk Moth muttered with a tone of reluctance, and a hint of fear, "Don't..."
"I shall summon a guardian," Mayura continued, "a beast born from your anger and hatred to deal with these heroes."
Hawk Moth resisted, but then gave in to her offer.
To Team Miraculous' complete shock, a giant moth creature appeared out of nowhere and blew them all away. This gave the butterfly villain the chance to escape and detransformed back into Gabriel.
He forgot the last time he was weary after detransforming. He completely forgot about his own weariness and quickly returned to his lair.
There, Catalyst was cradling an unconscious Marinette in her arms. Pinned to her shirt, was a familiar pin...
Marinette coughed weakly as Gabriel carried her into his office and settled her down on a chair.
"I warned you about using the Peacock Miraculous." Gabriel scolded as he knelt down beside her.
"I had no choice, Sir." Marinette replied weakly, "I had to help you."
"We told you it was damaged." Nathalie, now back to normal, reminded, "You could have suffered worse."
"I couldn't..." Marinette coughed, "I couldn't let Adrien find out..."
"Father!"
Upon hearing her classmate's voice, Marinette quickly took the Peacock Miraculous off her shirt and hid it just as a worried Adrien slammed the doors open.
"Father... Nathalie..." He rushed over and quickly hugged both adults.
Marinette gave a faint smile at the touching scene before her. The more reason he shouldn't know.
"Marinette..." He turned to his classmate and noticed she looked a little fatigued, "Are you okay?"
Marinette smiled, "Yeah. I'm... just relieved it's over."
"Yeah." Adrien remarked, "One way to celebrate Heroes' Day, huh?"
Marinette responded with an amused smile.
"I'll call your parents to pick you up." Nathalie informed Marinette.
"And I'll get you a glass of water." Adrien offered and left the room.
Once he was gone, Marinette brought out the Peacock Miraculous and looked at it with guilt.
"How long do you have to fight your own son?" She asked Gabriel without even lifting her head up.
Gabriel replied, "Until his and Ladybug's miraculouses belong to me."
She knew he would say that.
She could see the guilt in his eyes, but she knew that wasn't going to stop him from achieving his goal.
All she could do now, was to wait for the next akuma attack.
