SailorStar9: So, I was reliving my childhood by watching Bakusō Kyōdai Let's & Go when this plot bunny came to me and it's another 'before-Ami-became-a-Senshi' fic.

Disclaimers: I own not both animes or the pairing.

Plot Summary: What if Ami had been Dr. Tetshin's granddaughter? Because of the secrets of producing ZMC inked on her back, the retired Dr. Tetshin had Ami live with him to protect her from Dr. Ogami.

Prologue: New Machine of Flame: Tridagger Returns

"Living in the mountains for 10 years?" Gou muttered as the group trekked up the trail. "I don't understand him. Ouch! What's that for?" he exclaimed when a flood of potatoes rained on him.

"Potatoes…" Retsu blinked.

"But why would potatoes drop from the sky?" Gou wondered.

"Things would naturally fall from up to down." Tetshin explained on the cliff. "That is the law of gravity."

"Why do you do such things, old man?" Gou fumed.

"Everything's fallen to the ground." Tetshin chuckled. "It's quite troublesome for potatoes to fall from the basket."

"Jii-san..." Ami chided.

"Tetshin-sensei." Dr. Tsuchiya called.

"Oh, if it isn't Tsuchiya." Tetshin recognized his student. "It's been awhile. What are you doing here?"

"There's something I need your help with." Tsuchiya replied.

"That person is…" Retsu mused.

"Is that so?" Tetshin noted. "You're just in time. Pick up the potatoes first."

"Professor, there's a road for vehicles." Gou pointed out. "Can't we take the van here?"

"You still like to play such fun stuff." Tetshin chuckled. "So, what is it you want my help in?" he asked his guests, Ami having served the group tea.

"Actually, I want you to teach me the correct method of creating ZMC." Tsuchiya requested.

"ZMC?" Tetshin echoed. "What is that?"

"Jii-san…" Ami scolded.

"That's the new material you invented 10 years ago." Tsuchiya reminded.

"I know that." Tetshin teased. "You're still so impulsive. So then?"

"I wish to use ZMC to complete this machine." Tsuchiya pulled out the Tridagger model.

"I see." Tetshin nodded. "But as you can see, even if I agree, I'm merely a potter. I have nothing to do with race cars anymore."

"What's that?" Jirōmaru looked at the rows of pottery.

"They have such an eerie feel." Gou muttered.

"I beg you." Ryo bowed.

"Old man, I beg you, too." Gou followed suit.

"Sensei, I implore your help." Tsuchiya went on his knees.

"Please help my brother." Jirōmaru begged.

"Very well." Tetshin relented. "But, in exchange, you must work for me. You and the kid beside you, go and chop firewood. There's still some outside, right? Then, you two go clean the bathroom, it's in the back."

"Clean the bathroom?" Retsu whined.

"Hurry up and go!" Tetshin barked. "Tsuchiya, you can return now." He told his student, having sent the boys off. "Leave these kids to me."

"I apologize for my grandfather." Ami stated, the Takaba siblings having settled down on the corridor for a break. "That's just how he is."

"He has an… interesting personality." Ryo admitted.

"I still say he's weird." Jirōmaru muttered.

"Jirōmaru!" Ryo scolded. "I apologize for my brother."

"Actually, he won't be the first one to say that." Ami giggled. "And definitely won't be the last."

"I'm surprised you're taking this in stride." Ryo noted, as he heaved the bucket of water from the well.

"You get used to it," Ami shrugged. "Especially if you've been living here for the last 8 years."

"The water isn't hot enough." Tetshin stated in the tub. "Add more firewood."

"Such a whiner." Jirōmaru complained.

"Looks like I won't teach you to make ZMC." Tetshin warned.

"I've already added in firewood." Gou whined.

"I'm sorry." Ryo apologized. "I dragged you into this."

"It's nothing." Retsu assured. "It's all for Neo Tridagger."

"Alright," Gou whooped. "Let's work harder before dinner."

"Now I think of it," Tetshin sipped his sake as the group sat for dinner. "What do you intend to do once the machine's finished? To get revenge?"

"That goes without saying?" Gou cut in. "Right, Ryo?"

"That's right." Ryo agreed. "Taking revenge is a must."

"We must shake him off very far away." Gou added.

"Once Tridagger is revived, we can definitely win." Retsu concurred.

"That's right." Jirōmaru nodded. "Tridagger's speed is certainly exceptional, right big brother?"

"That's right." Ryo nodded." I won't lose to Beak Spider."

"Speed, huh?" Tetshin mused. "Don't you want to destroy your opponent's car?"

"What's the use of doing that?" Gou inquired.

"No, that's…" Tetshin chuckled and sipped his sake. "This is a nice flavour."

"Didn't you bury that sake pot for 10 years, grandfather?" Ami reminded.

They're a bunch of interesting kids. Tetshin mused, sipping his wine. I'm beginning to understand why Tsuchiya chose them. Very well, I'll give them a hand.

"Jii-san, you're bringing that out?" Ami echoed, the group gathered outside the shack.

"The three of you, come along too." Tetshin instructed, carrying the sealed pot under his arm.

"What is in this place?" Gou wondered, Tetshin leading the children into the cave.

"This is the passage for a secret underground factory during the war." Ami explained.

"Underground factory?" Gou echoed.

"Take this for me." Tetshin handled Gou the flashlight once the group arrived at the kiln and switched on the generator.

"This is the kiln for creating ZMC." Tetshin replied. "I spent quite a lot of energy to transport it here 10 years ago. Looks like the effort isn't wasted. The reason why Tsuchiya couldn't create ZMC is because he is too stickler, just like before."

"What are you doing?" Gou asked, Tetshin having fished out the Tridagger model out of the liquid in the pot.

"If you don't apply this coat of specialized medicinal liquid, ZMC won't solidify." Tetshin explained.

"That's why Professor Tsuchiya failed." Retsu realized.

"Now," Tetshin shut the kiln's door. "You can achieve the great power of ZMC. But, if you use this power in the wrong way, it will harm you and the others around you. I've seen such examples way too many times. You have no problem with that?"

"Yes." Ryo nodded.

"Then, I'll believe you." Tetshin replied. "So then…" he stepped on a lever, the car's body taking shape within the furnace.

"Err, Jii-san …" Ami muttered at the connecting pipes started clattering. "We have a problem…"

"It's suddenly became louder." Jirōmaru added.

"Retreat now! Tetshin gave the order once the pips started breaking down.

"I knew it!" Ami exclaimed, the group fleeing outside just as the kiln exploded. "Jii-san, didn't I tell you to maintain that particular kiln?"

"What about Tridagger?" Gou thought to ask.

"Could it have been blown to bits?" Jirōmaru wondered.

"Perhaps." Tetshin nodded.

"Now what?" Gou complained.

"Hand the flashlight over." Tetshin instructed. "Wait for me." He added and entered the smoking cave.

"He's out." Ami spotted her grandfather.

"It's done." Tetshin showed them the car body. "ZMC has been created."

"Amazing." Gou gushed.

"That's nothing." Tetshin grinned.

"Old man, I've underestimated you." Jirōmaru gaped.

"That's amazing." Retsu gasped. "That's Professor Tsuchiya's teacher for you."

"Tetshin-sensei, I thank you." Ryo bowed.

"That's nothing." Tetshin chided. "It's your sincerity that revived your machine." And handed Ryo the new car body.

"Jii-san, bend down any more, and you'll really sprain your back." Ami reminded.

"My… back…" Tetshin gaped, his spine threatening to break.

"Jii-san…" Ami shook her head.

SailorStar9: Now that's done, read and review.