After what happened at the police station the other night, the gang could see they had another mystery on their hands. A mysterious figure known as the Fiend has stolen some costumes and is well aware of the gang and what they'll try to do. They all met up at Natsu's house with them all seeing what happened on the news and tried to figure out what could be going on?"

"Well, we certainly have another mystery on our hands." Gray said. "However, I can't figure out what someone would want from all that."

"The Fiend stole five costumes from the police station, costumes of villains we put away." Erza said. "What would anyone want with that stuff?"

"The Fiend obviously knows about us. He called us out. Do you guys think it's possible that the Fiend is really someone we put away before?" Gray said.

"Maybe, or it could be someone who holds a connection to one of them." Lucy said.

"So much for our big celebration." Natsu said. "This was going to be a great time for us. Now this guy comes around he ruins all of it."

"Don't worry, Natsu. The sooner we solve the mystery, the sooner we can get back to the celebrating." Lucy said. "We just need a clue to what's going on." Just when she said that, they all heard a thumping sound from upstairs. It sounded like something fell on the floor.

"What was that?" Gray said.

"It sounded like it came from Zeref's room." Natsu said.

"I didn't know your brother was here." Erza said.

"He's not. He left with my parents." Natsu said. All of them thought this was rather weird. They all moved carefully up the stairs to see what the sound was. Once they reached Zeref's room, they opened the door carefully to see anything out of the ordinary, but there was no one there. Happy even acted like a cop with him holding his finger like a gun.

"Nothing." Gray said as none of them saw anyone in there.

"There it is." Lucy said as she spotted a black book on the floor and grabbed it. "Something probably just knocked this book over." She was about to put it away until she noticed something strange about it. "Natsu, what kind of book is this?"

"I don't know. It must be one of his college books." Natsu said.

"This doesn't look like a college book." Lucy said as she was getting an ominous feeling from looking at that book. She opened up to see what was inside and it looked rather strange and suspicious.

"What is it, Lucy? What's in there?" Gray questioned.

"These equations... These formulas... There's even steps to building a body." Lucy said as she wasn't liking the looks of this at all. She couldn't believe what she was reading. "This is an instruction manual to create monsters! Something like Frankenstein!"

"What?! No way!" Gray said as he had a look at it himself. "No way this is for real. This has to be some sort of joke."

"I don't know. This looks pretty authentic." Lucy said.

"Natsu, what does your brother study in college?" Erza asked.

"Well, he does study science. His specialty seems to be in biology." Natsu said.

"Biology? You mean the study of life?" Lucy said as that all sounded rather eerie with what they just found.

"Hold on. Just because that's what he studies doesn't mean he's got anything to do with this." Natsu said as he didn't think his brother would do anything like this. Still, it did seem rather strange and suspicious that someone getting a degree in science with his specialty being biology would have something like the book. Before they could talk about it anymore, they all had their phones go off and they each got a message.

"That's weird. I just got a message from my parents saying they want to meet all of us at the park." Lucy said.

"I just got the same message from my mother." Erza said.

"We all got the same message." Gray said. "What could our parents want with us now?"

"Let's just go and find out." Natsu said as they all did what their parents said. Lucy just tossed the book on Zeref's bed and left it, but that book could be more important than they think.

...

The Park

The gang headed for the park like their parents told them. They were all rather curious as to what their parents could want with them now since they have a mystery to solve. When they arrived at the park, they all looked around for them.

"Hello! Is anyone here?!" Natsu called as they searched around for their parents.

"Surprise!" All their parents came out and it looked like a party.

"What is this?" Lucy said with all of them pleasantly surprised. "It's none of our birthdays today."

"We know. This is a party for all of you." Layla said.

"We understand that you're busy with solving another mystery after what happened last night, but we wanted to do this for all of you." Irene said.

"It's to celebrate you kids getting a spot in the museum." Silver said. "We're all so proud of all of you that we wanted to celebrate it right."

"That's nice, but we're in the middle of solving a... Is that strawberry cake?!" Erza said as they already lost her. Seeing as how their parents did went through all this trouble, the rest of them fell in line and just decided to have fun with the party. All of them joined in the celebration with the parents being so proud of their kids.

"Hold on. Where's Zeref?" Natsu asked as they all gathered around for some food. "I thought we was with the two of you."

"He was helping us out. In fact, he should be here partying with the rest of us." Igneel said.

"All of a sudden, he said he had something else to take care of." Heather said. That did seem rather strange given what the gang found, but Natsu refuses to believe his own brother could be the one behind all of this. While they were all talking about this, Happy thought he spotted something moving behind the trees. Being the detective cat he is, he went over to check it out.

"Happy? What are you doing?" Natsu said as he noticed it and everyone was looking at him. Happy moved a little closer to what he saw.

"Surprise!" Happy got a good scare and ran back when they all saw it was the Fiend.

"It's him!" Erza said as they all braced themselves for whatever he wants.

"A party that I wasn't invited to? Not very nice." The Fiend said.

"What do you want?" Gray said.

"Just to terrify all of you!" The Fiend said as he gave off a sinister laugh.

"Let's get out of here!" Layla said as they all thought as parents and wanted to get out of there. They all ran for it until a familiar face got in their way and laughed. The gang couldn't believe who it was.

"It's the Fiend Hatter!" Lucy said.

"Who?" Jude questioned.

"He's one of the villains we unmasked!" Gray said.

"And he's not alone." Natsu said as he spotted a large black cat stepping out and giving off a frightening roar.

"Panther Guardian! He's not even from this country!" Erza said. Seeing two of the old enemies was quite a surprise. They all backed away, but Gray backed right into someone large and another figure giving off a shrieking sound. He moved away from them and saw who they were.

"The Oni and Man-Bat?!" Gray said as they were surprised to see them too.

"Head for the lake!" Silver said. They all tried running to the water, but Happy spotted something in the water and tried to warn them about it. Natsu took a look and saw who was climbing out of the water.

"It's the Horned Man!" The Horned Man himself made it out of the water and now they were all surrounded by five of their old enemies.

"Is this normal for you and your friends, Lucy? I'm not sure I want you to solve mysteries anymore." Layla said.

"Well, we might have made a few enemies." Lucy said.

"How right you are, my dear." The Fiend said as he had them all right where they wanted him. He motioned for all the monsters to come closer and they all looked ready to attack them.

"Hold on. There's no reason to be afraid." Gray said.

"Huh? Why?" Silver asked.

"These are the five costumes that were stolen from the police." Gray said. "They're just more creeps in costumes, all fakes."

"Nice try, freak. You can't scare us that easily." Natsu said as they all believe they saw right through them. Happy was the brave one to show them all as he made his way over to the Man-Bat. He climbed right on top of him and tried pulling off his mask, but something wasn't right. The mask wasn't coming off. "Happy, quit playing around and pull the mask off." Happy was trying to tell them he wasn't playing. The Man-Bat gave off a ear-breaking shriek right at Happy and scared Happy away from him. All five of them weren't acting like people in costumes. The Fiend laughed as the gang could not understand what is going on.

"This is one mystery you won't be able to solve so easily." The Fiend said.

"Well, there's one thing you didn't think of." Erza said with the Fiend not getting it. "There's a lot more of us!" They all followed Erza's lead as they all ran right through him like they were a stampede and gave him a good spin.

"Get them!" The Fiend ordered the monsters with all of them going after a member of the gang and their parents.

...

The Dragneels

The Oni chased after Natsu and his parents. He had Heather and Igneel trapped and it seemed like nothing could help them.

"Hurry! Hurry! Hurry! Step right up and test your strength!" Natsu called as he acted like a carny and even had a test your strength game. "How about you good, sir? Want to give it a try?" The Oni questioned if he meant him. "Yes, you. It's easy." He said as he tried showing the Oni how it's done. "You just lift this hammer and go like this!" He lifted the hammer, but smashed it against the Oni's foot. As he screamed in pain, Natsu and his parents ran for it.

"How did you do that?" Igneel questioned.

"Don't question it! Just run for it!" Natsu said.

...

The Heartfilias

Lucy and her family took cover from the monsters themselves. They kept their eyes open for any of them.

"Lucy, what is going on?" Jude questioned.

"I wish I knew." Lucy said. "That's part of solving mysteries, Dad. You have to try and figure out the answers yourselves."

"Oh my gosh!" Layla called out with them hurrying to her thinking she was in trouble. "A dress that gorgeous that's half the price?! How is that still for sale?!"

"Mom..." Lucy said as she and Jude couldn't believe she would act in such a way now. Of course, real terror came at them as they saw the Fiend Hatter's reflection in the window. They all moved away as he came at them. As he went after Lucy's parents, Lucy she knew she had to do something. She looked around and tried to think of some way to save them and spotted something that could help. She just needed to move a few things out of the way. "Hey! Come and get me!" She called with the Fiend Hatter going at her.

"Lucy!" Layla called with her parents worried on what might happen to her. The Fiend Hatter charged right at her, but she moved away at the last second and he nearly fell into an open manhole. As he tried gaining his balance over the edge, Lucy just poked him and he fell right inside with the Heartfilias having a chance to run.

...

The Fullbusters

Gray and his father were running through the streets as well. They looked around, but didn't see any of the monsters anywhere.

"Do you see them?" Silver said.

"I think we lost them." Gray believed, but he just jinxed it when they heard shrieking. They looked up and saw the Man-Bat flying right at them. They acted fast as they ducked down and avoided him. "He didn't do that before!" The Man-Bat came back around and tried grabbing at them again, but the avoided him again. Gray had to think fast to lose that bat. He looked around for something that he could use. "Dad, over here!" He grabbed Silver and they both hurried behind a building with the Man-Bat flying after them.

"Here it comes!" Silver said as they waited for it. They both moved out of the way with the Man-Bat crashing into a dumpster and both of them closed it on him

...

The Scarlets

Erza and Irene ducked inside a clothing store. They thought they were safe inside.

"Are you sure we're safe in here?" Irene asked.

"For now at least. They always have a way of coming back." Erza said. As they kept their guard up for anything, Erza spotted a strange looking mannequin. "What's with that mannequin? It looks like..." It looked like the Horned Man because it was him. He started moving and moved closer to them.

"Any ideas?" Irene said as they tried backing away from him. Erza tried to think of something and she soon got it. She took a bunch of jackets and tied them together.

"You look a little cold." Erza said as she threw the jackets over him and the Horned Man got tangled in them. As he struggled to get out, Erza and her mother were able to escape from it.

...

Happy

As for poor Happy, he was on his own while Panther Guardian was on the hunt. He hunt Happy down to a toy store and tried to find him. What he didn't see was that Happy was posing as a stuffed animal. Happy tried his best to stay still as Panther Guardian searched around for him. Of course, with rotten luck, Happy felt a sneeze coming and couldn't hold it back. That's what alerted Panther Guardian as to where he was. Happy tried making a run for it, but Panther Guardian reached out and grabbed a hold of him. However, Happy did grab a toy suction cup gun. When Happy was turned to Panther Guardian's face, he shot Panther Guardian right in the eyes and was able to escape. They all might have been able to ditch those monsters, but this isn't over. The gang is being hunted down by figures from their past, and it seems like they're back for revenge.