The library echoed with the lonely footsteps of a security guard making his rounds. The fluorescent lights cast eerie shadows, flickering every so often as if to remind him of the countless ghost stories set in such places. "Most boring job in Coolsville," he muttered to himself, stifling a yawn. His flashlight beam swept across the rows of dusty books until it stopped on an unexpected sight: a female puppet perched on a table.

"What are you doing here, little miss?" he asked, puzzled. As if in response, the puppet's eyes snapped open, and it lifted a tiny wooden arm, pointing behind him.

Before he could react, the security guard turned, only to be met with the chilling sight of a figure dressed in jester attire, its expression frozen in a sinister smile. "AHHH!" he screamed, dropping his flashlight as the figure advanced.

The next morning, Coolsville International Airport buzzed with activity. Amidst the travelers, a plane taxied to the gate, and the first to disembark was a 15-year-old Japanese girl with a distinctive pink streak in her hair. Clad in a pink shirt and shorts, she was easy to spot.

"Jade!" a voice called out, and Jade turned to see a white cat in a pet carrier, its green eyes sharp and inquisitive.

"Sorry, Mitsu," Jade said, adjusting the carrier in her hand.

Mitsu, the cat, huffed in disapproval. "I still can't believe you chose Coolsville for your semester abroad. Why couldn't you have chosen Townsville, Royal Woods, or even Bellwood?"

Jade smiled, a spark of excitement in her eyes. "Because Coolsville is the most popular hotspot for supernatural activity. There's no place I'd rather be."

"You and the supernatural," Mitsu said with a mix of fondness and exasperation, peering through the pet carrier's bars.

Outside the airport, the bustling activity of Coolsville greeted them. Jade and Mitsu were met by a girl around Jade's age, with short brown hair, an orange sweater, a red skirt, and glasses that framed her intelligent eyes.

"こんにちは! You must be Velma Dinkley," Jade said, bowing slightly in greeting.

"Yes, and you must be Jade Tezuka," Velma replied, extending a hand with a friendly smile.

"Yes, and this is my cat, Mitsu," Jade said, lifting the carrier slightly to introduce her furry companion.

"Hi," Mitsu meowed, causing Velma to raise an amused eyebrow.

Later, as the sun began to set, Velma took Jade and Mitsu on a tour of Coolsville. The town was a blend of quaint charm and vibrant energy, with bustling streets and a rich history evident in its architecture. They walked past charming shops, colorful murals, and lively parks, each corner revealing more of the town's character.

"Wow, Coolsville is amazing," Jade said, her eyes wide with wonder as she took in the sights.

Velma nodded, her own enthusiasm evident. "There's so much to see and do here. And don't worry, we'll get to the bottom of any supernatural mysteries that come our way."

Suddenly they saw the Coolsville library having police around it.

The two approach the sheriff.

"Sheriff Bronson Stone. What happened?" Velma asked.

"Well apparently the library is now haunted by a puppeteer librarian." Sheriff stone said "The security guard saw it last night and ran off screaming like a baby."

"Any leads?" Velma asked.

"None so far. I assume this is where you and your clue company come in?" Sheriff Stone asked.

"We're called Mystery Incorporated. And yes." Velma said as she pulled out her phone. "Gang we got another mystery on our hands."

Suddenly a van with the words Mystery Machine arrived.

Three people and a great dane came out of it.

the first one was a blonde male in a white shirt and blue pants with a orange ascot around his neck.

the second was a red hair female wearing a purple dress and a green scarf.

the third was a brown hair male wearing a green shirt.

The Great Dane had a collar with a tag that had the letters S and D on it.

"Jade this is Fred daphne Shaggy and Scooby Doo." Velma said.

"Nice to meet you all." Jade said.

"Well I'll leave you kiddos to the mystery. Call me as soon as you catch the culprit." Sheriff Stone said as he and the police soon left.

Later the group were in the library.

"Alright gang lets split up and look for clues." Fred said.

"Like i knew he would say that." Shaggy said.

Shaggy Scooby Velma Jade and mitsu were searching the kids corner for clues.

"Wow this is so exciting." Jade said.

"Remember look for clues." Velma said.

"I would rather relax in my cat post back home in Japan." Mitsu said as she was in a little chair.

Jade pulled out a book and the bookcase moved and reveal a secret passage.

"Like secret passages always led to trouble." Shaggy said as he and scooby huddled in fear.

"Come on you two." Velma said.

Soon they enter the secret passage and found a makeshift living area.

"Strange. Why would all this be doing under a library?" Velma said.

Shaggy and Scooby Doo soon notice a mini fridge.

"Like who said anything about food under the library." Shaggy said as he pulled out a sandwich.

"Americans." Mitsu said in annoyance.

Velma and Jade looked around and saw a photo of a elderly man which velma quickly recognized.

"Pietro aka The Puppet Master. He was one of the previous mystery solving group's most famous case." Velma said.

"There were more groups like yours?" Jade asked.

"Indeed." Velma said.

"Do you think Pietro is behind this?" Jade asked.

"Unlikely Pietro is retired and is in Florida." Velma said as she noticed a puppet with a red hat.

Soon the puppet's eyes open stood up and pointed behind Velma and Jade.

Velma and Jade looked behind them and saw the Puppeteer jester.

The two girls screamed and quickly ran.

"Like I thought you were supposed to be quiet in a library." Shaggy said as he noticed the puppeteer jester.

Soon Shaggy Scooby Doo and Mitsu soon join Velma and Jade in running.

Soon the group ran into Fred and Daphne.

"Hey guys. Did ya find any clues?" Daphne asked.

"Well it seems that whoever is behind this idolizes Pietro AKA The Puppet Master." Velma said.

"Interesting. We found this." Fred said as he handed Velma the female puppet the security guard encountered.

Velma examined the puppet and foubd a device attached to it.

"Fascinating." Velma said.

"It appears to be some kind of controlling device." Jade said.

"Gang it's time to solve this mystery." Velma said.

The Puppeteer jester was searching whwn it spotted Shaggy and Scooby reading.

It approached them but suddenly it slipped on a skateboard causing it to crash right into a net and it went up as soon as the jester crashed into it.

Later the police came.

"Mystery Inc once again you solved a case." Sheriff Stone said.

"Thanks now let's see who this jester really is." Fred said as he removed the jester's mask revealing a woman with brown hair.

"Sofia Pietro the daughter of Jacob Pietro AKA the puppet master. After her father was arrested she spent her life plotting her revenge on Coolsville using a special control device she stole fron Quest Labs she used her father's puppets to scare off anyone in the library and lure us the current mystery solving group to investigate." Velma explained.

"And I've would've gotten away with it if it wasn't for you meddling kids your dog and the meddlers from Japan." Sofia said as she was escorted to the police car.

The next day the gang were celebrating not just solving the mystery but also welcoming Jade and Mitsu to the team.

"I still can't believe you agreed to join mystery inc." Mitsu said.

"Come on Mitsu it'll be fun." Jade said.

Mitsu sighed in defeat knowing that this will be a wild year.